only validate tool name

## Description

This pull request adds a new tool, cloud-sql-restore-backup, which
enables restoring a backup onto a Cloud SQL instance from the toolbox
using the Cloud SQL Admin API. The tool supports restoring standard,
project level, and BackupDR backups.

Tested:
<img width="3758" height="532" alt="image"
src="https://github.com/user-attachments/assets/d1d61af7-d96e-417c-898c-65b876de4c5e"
/>


## PR Checklist

> Thank you for opening a Pull Request! Before submitting your PR, there
are a
> few things you can do to make sure it goes smoothly:

- [x] Make sure you reviewed

[CONTRIBUTING.md](https://github.com/googleapis/genai-toolbox/blob/main/CONTRIBUTING.md)
- [x] Make sure to open an issue as a

[bug/issue](https://github.com/googleapis/genai-toolbox/issues/new/choose)
  before writing your code! That way we can discuss the change, evaluate
  designs, and agree on the general idea
- [x] Ensure the tests and linter pass
- [x] Code coverage does not decrease (if any source code was changed)
- [x] Appropriate docs were updated (if necessary)
- [x] Make sure to add `!` if this involve a breaking change

🛠️ Fixes #2170

Co-authored-by: Averi Kitsch <akitsch@google.com>

CONTRIBUTING.md

@@ -92,11 +92,11 @@ implementation](https://github.com/googleapis/genai-toolbox/blob/main/internal/s
   `newdb.go`. Create a `Config` struct to include all the necessary parameters
   for connecting to the database (e.g., host, port, username, password, database
   name) and a `Source` struct to store necessary parameters for tools (e.g.,
-  Name, Type, connection object, additional config).
+  Name, Kind, connection object, additional config).
 * **Implement the
   [`SourceConfig`](https://github.com/googleapis/genai-toolbox/blob/fd300dc606d88bf9f7bba689e2cee4e3565537dd/internal/sources/sources.go#L57)
   interface**. This interface requires two methods:
-  * `SourceConfigType() string`: Returns a unique string identifier for your
+  * `SourceConfigKind() string`: Returns a unique string identifier for your
     data source (e.g., `"newdb"`).
   * `Initialize(ctx context.Context, tracer trace.Tracer) (Source, error)`:
     Creates a new instance of your data source and establishes a connection to
@@ -104,7 +104,7 @@ implementation](https://github.com/googleapis/genai-toolbox/blob/main/internal/s
 * **Implement the
   [`Source`](https://github.com/googleapis/genai-toolbox/blob/fd300dc606d88bf9f7bba689e2cee4e3565537dd/internal/sources/sources.go#L63)
   interface**. This interface requires one method:
-  * `SourceType() string`: Returns the same string identifier as `SourceConfigType()`.
+  * `SourceKind() string`: Returns the same string identifier as `SourceConfigKind()`.
 * **Implement `init()`** to register the new Source.
 * **Implement Unit Tests** in a file named `newdb_test.go`.
 
@@ -126,7 +126,7 @@ tools.
 * **Implement the
   [`ToolConfig`](https://github.com/googleapis/genai-toolbox/blob/fd300dc606d88bf9f7bba689e2cee4e3565537dd/internal/tools/tools.go#L61)
   interface**. This interface requires one method:
-  * `ToolConfigType() string`: Returns a unique string identifier for your tool
+  * `ToolConfigKind() string`: Returns a unique string identifier for your tool
     (e.g., `"newdb-tool"`).
   * `Initialize(sources map[string]Source) (Tool, error)`: Creates a new
     instance of your tool and validates that it can connect to the specified
@@ -243,7 +243,7 @@ resources.
   | style           | Update src code, with only formatting and whitespace updates (e.g. code formatter or linter changes). |
 
   Pull requests should always add scope whenever possible. The scope is
-  formatted as `<scope-resource>/<scope-type>` (e.g., `sources/postgres`, or
+  formatted as `<scope-type>/<scope-kind>` (e.g., `sources/postgres`, or
   `tools/mssql-sql`).
   
   Ideally, **each PR covers only one scope**, if this is

README.md

@@ -954,7 +954,7 @@ For more details on configuring different types of sources, see the
 ### Tools
 
 The `tools` section of a `tools.yaml` define the actions an agent can take: what
-type of tool it is, which source(s) it affects, what parameters it uses, etc.
+kind of tool it is, which source(s) it affects, what parameters it uses, etc.
 
 ```yaml
 tools:

cmd/root.go

@@ -15,7 +15,6 @@
 package cmd
 
 import (
-	"bytes"
 	"context"
 	_ "embed"
 	"fmt"
@@ -99,6 +98,7 @@ import (
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlgetinstances"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqllistdatabases"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqllistinstances"
+	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlrestorebackup"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlwaitforoperation"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsqlmssql/cloudsqlmssqlcreateinstance"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsqlmysql/cloudsqlmysqlcreateinstance"
@@ -395,6 +395,7 @@ func NewCommand(opts ...Option) *Command {
 
 type ToolsFile struct {
 	Sources         server.SourceConfigs         `yaml:"sources"`
+	AuthSources     server.AuthServiceConfigs    `yaml:"authSources"` // Deprecated: Kept for compatibility.
 	AuthServices    server.AuthServiceConfigs    `yaml:"authServices"`
 	EmbeddingModels server.EmbeddingModelConfigs `yaml:"embeddingModels"`
 	Tools           server.ToolConfigs           `yaml:"tools"`
@@ -425,106 +426,6 @@ func parseEnv(input string) (string, error) {
 	return output, err
 }
 
-func convertToolsFile(ctx context.Context, raw []byte) ([]byte, error) {
-	var input yaml.MapSlice
-	decoder := yaml.NewDecoder(bytes.NewReader(raw), yaml.UseOrderedMap())
-	if err := decoder.Decode(&input); err != nil {
-		return nil, err
-	}
-
-	// Convert raw MapSlice to a helper map for quick lookup
-	// while keeping the values as MapSlices to preserve internal order
-	resourceOrder := []string{}
-	lookup := make(map[string]yaml.MapSlice)
-	for _, item := range input {
-		key, ok := item.Key.(string)
-		if !ok {
-			return nil, fmt.Errorf("unexpected non-string key in input: %v", item.Key)
-		}
-		if slice, ok := item.Value.(yaml.MapSlice); ok {
-			// convert authSources to authServices
-			if key == "authSources" {
-				key = "authServices"
-			}
-			// works even if lookup[key] is nil
-			lookup[key] = append(lookup[key], slice...)
-			// preserving the resource's order of original toolsFile
-			if !slices.Contains(resourceOrder, key) {
-				resourceOrder = append(resourceOrder, key)
-			}
-		} else {
-			// toolsfile is already v2
-			if key == "kind" {
-				return raw, nil
-			}
-			return nil, fmt.Errorf("'%s' is not a map", key)
-		}
-	}
-	// convert to tools file v2
-	var buf bytes.Buffer
-	encoder := yaml.NewEncoder(&buf)
-	for _, kind := range resourceOrder {
-		data, exists := lookup[kind]
-		if !exists {
-			// if this is skipped for all keys, the tools file is in v2
-			continue
-		}
-		// Transform each entry
-		for _, entry := range data {
-			entryName, ok := entry.Key.(string)
-			if !ok {
-				return nil, fmt.Errorf("unexpected non-string key for entry in '%s': %v", kind, entry.Key)
-			}
-			entryBody := ProcessValue(entry.Value, kind == "toolsets")
-
-			transformed := yaml.MapSlice{
-				{Key: "kind", Value: kind},
-				{Key: "name", Value: entryName},
-			}
-
-			// Merge the transformed body into our result
-			if bodySlice, ok := entryBody.(yaml.MapSlice); ok {
-				transformed = append(transformed, bodySlice...)
-			} else {
-				return nil, fmt.Errorf("unable to convert entryBody to MapSlice")
-			}
-
-			if err := encoder.Encode(transformed); err != nil {
-				return nil, err
-			}
-		}
-	}
-	return buf.Bytes(), nil
-}
-
-// ProcessValue recursively looks for MapSlices to rename 'kind' -> 'type'
-func ProcessValue(v any, isToolset bool) any {
-	switch val := v.(type) {
-	case yaml.MapSlice:
-		for i := range val {
-			// Perform renaming
-			if val[i].Key == "kind" {
-				val[i].Key = "type"
-			}
-			// Recursive call for nested values (e.g., nested objects or lists)
-			val[i].Value = ProcessValue(val[i].Value, false)
-		}
-		return val
-	case []any:
-		// Process lists: If it's a toolset top-level list, wrap it.
-		if isToolset {
-			return yaml.MapSlice{{Key: "tools", Value: val}}
-		}
-		// Otherwise, recurse into list items (to catch nested objects)
-		for i := range val {
-			val[i] = ProcessValue(val[i], false)
-		}
-		return val
-	default:
-		return val
-	}
-}
-
 // parseToolsFile parses the provided yaml into appropriate configs.
 func parseToolsFile(ctx context.Context, raw []byte) (ToolsFile, error) {
 	var toolsFile ToolsFile
@@ -535,13 +436,8 @@ func parseToolsFile(ctx context.Context, raw []byte) (ToolsFile, error) {
 	}
 	raw = []byte(output)
 
-	raw, err = convertToolsFile(ctx, raw)
-	if err != nil {
-		return toolsFile, fmt.Errorf("error converting tools file: %s", err)
-	}
-
 	// Parse contents
-	toolsFile.Sources, toolsFile.AuthServices, toolsFile.EmbeddingModels, toolsFile.Tools, toolsFile.Toolsets, toolsFile.Prompts, err = server.UnmarshalResourceConfig(ctx, raw)
+	err = yaml.UnmarshalContext(ctx, raw, &toolsFile, yaml.Strict())
 	if err != nil {
 		return toolsFile, err
 	}
@@ -573,6 +469,18 @@ func mergeToolsFiles(files ...ToolsFile) (ToolsFile, error) {
 			}
 		}
 
+		// Check for conflicts and merge authSources (deprecated, but still support)
+		for name, authSource := range file.AuthSources {
+			if _, exists := merged.AuthSources[name]; exists {
+				conflicts = append(conflicts, fmt.Sprintf("authSource '%s' (file #%d)", name, fileIndex+1))
+			} else {
+				if merged.AuthSources == nil {
+					merged.AuthSources = make(server.AuthServiceConfigs)
+				}
+				merged.AuthSources[name] = authSource
+			}
+		}
+
 		// Check for conflicts and merge authServices
 		for name, authService := range file.AuthServices {
 			if _, exists := merged.AuthServices[name]; exists {
@@ -1048,6 +956,20 @@ func run(cmd *Command) error {
 	cmd.cfg.ToolsetConfigs = finalToolsFile.Toolsets
 	cmd.cfg.PromptConfigs = finalToolsFile.Prompts
 
+	authSourceConfigs := finalToolsFile.AuthSources
+	if authSourceConfigs != nil {
+		cmd.logger.WarnContext(ctx, "`authSources` is deprecated, use `authServices` instead")
+
+		for k, v := range authSourceConfigs {
+			if _, exists := cmd.cfg.AuthServiceConfigs[k]; exists {
+				errMsg := fmt.Errorf("resource conflict detected: authSource '%s' has the same name as an existing authService. Please rename your authSource", k)
+				cmd.logger.ErrorContext(ctx, errMsg.Error())
+				return errMsg
+			}
+			cmd.cfg.AuthServiceConfigs[k] = v
+		}
+	}
+
 	instrumentation, err := telemetry.CreateTelemetryInstrumentation(versionString)
 	if err != nil {
 		errMsg := fmt.Errorf("unable to create telemetry instrumentation: %w", err)

cmd/root_test.go

@@ -23,14 +23,12 @@ import (
 	"os"
 	"path"
 	"path/filepath"
-	"reflect"
 	"regexp"
 	"runtime"
 	"strings"
 	"testing"
 	"time"
 
-	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 
 	"github.com/googleapis/genai-toolbox/internal/auth/google"
@@ -496,309 +494,6 @@ func TestDefaultLogLevel(t *testing.T) {
 	}
 }
 
-func TestConvertToolsFile(t *testing.T) {
-	ctx, cancelCtx := context.WithTimeout(context.Background(), time.Minute)
-	defer cancelCtx()
-	pr, pw := io.Pipe()
-	defer pw.Close()
-	defer pr.Close()
-
-	logger, err := log.NewStdLogger(pw, pw, "DEBUG")
-	if err != nil {
-		t.Fatalf("failed to setup logger %s", err)
-	}
-	ctx = util.WithLogger(ctx, logger)
-
-	tcs := []struct {
-		desc   string
-		in     string
-		want   string
-		isErr  bool
-		errStr string
-	}{
-		{
-			desc: "basic convert",
-			in: `
-            sources:
-                my-pg-instance:
-                    kind: cloud-sql-postgres
-                    project: my-project
-                    region: my-region
-                    instance: my-instance
-                    database: my_db
-                    user: my_user
-                    password: my_pass
-            authServices:
-                my-google-auth:
-                    kind: google
-                    clientId: testing-id
-            tools:
-                example_tool:
-                    kind: postgres-sql
-                    source: my-pg-instance
-                    description: some description
-                    statement: |
-                      SELECT * FROM SQL_STATEMENT;
-                    parameters:
-                        - name: country
-                          type: string
-                          description: some description
-            toolsets:
-                example_toolset:
-                    - example_tool
-            prompts:
-                code_review:
-                    description: ask llm to analyze code quality
-                    messages:
-                      - content: "please review the following code for quality: {{.code}}"
-                    arguments:
-                        - name: code
-                          description: the code to review
-            embeddingModels:
-                gemini-model:
-                    kind: gemini
-                    model: gemini-embedding-001
-                    apiKey: some-key
-                    dimension: 768`,
-			want: `
-kind: sources
-name: my-pg-instance
-type: cloud-sql-postgres
-project: my-project
-region: my-region
-instance: my-instance
-database: my_db
-user: my_user
-password: my_pass
----
-kind: authServices
-name: my-google-auth
-type: google
-clientId: testing-id
----
-kind: tools
-name: example_tool
-type: postgres-sql
-source: my-pg-instance
-description: some description
-statement: |
-    SELECT * FROM SQL_STATEMENT;
-parameters:
-- name: country
-  type: string
-  description: some description
----
-kind: toolsets
-name: example_toolset
-tools:
-- example_tool
----
-kind: prompts
-name: code_review
-description: ask llm to analyze code quality
-messages:
-- content: "please review the following code for quality: {{.code}}"
-arguments:
-- name: code
-  description: the code to review
----
-kind: embeddingModels
-name: gemini-model
-type: gemini
-model: gemini-embedding-001
-apiKey: some-key
-dimension: 768`,
-		},
-		{
-			desc: "preserve resource order with grouping",
-			in: `
-            tools:
-                example_tool:
-                    kind: postgres-sql
-                    source: my-pg-instance
-                    description: some description
-                    statement: |
-                        SELECT * FROM SQL_STATEMENT;
-                    parameters:
-                        - name: country
-                          type: string
-                          description: some description
-            sources:
-                my-pg-instance:
-                    kind: cloud-sql-postgres
-                    project: my-project
-                    region: my-region
-                    instance: my-instance
-                    database: my_db
-                    user: my_user
-                    password: my_pass
-            authServices:
-                my-google-auth:
-                    kind: google
-                    clientId: testing-id
-            toolsets:
-                example_toolset:
-                    - example_tool
-            authSources:
-                my-google-auth:
-                    kind: google
-                    clientId: testing-id`,
-			want: `
-kind: tools
-name: example_tool
-type: postgres-sql
-source: my-pg-instance
-description: some description
-statement: |
-    SELECT * FROM SQL_STATEMENT;
-parameters:
-- name: country
-  type: string
-  description: some description
----
-kind: sources
-name: my-pg-instance
-type: cloud-sql-postgres
-project: my-project
-region: my-region
-instance: my-instance
-database: my_db
-user: my_user
-password: my_pass
----
-kind: authServices
-name: my-google-auth
-type: google
-clientId: testing-id
----
-kind: authServices
-name: my-google-auth
-type: google
-clientId: testing-id
----
-kind: toolsets
-name: example_toolset
-tools:
-- example_tool`,
-		},
-		{
-			desc: "no convertion needed",
-			in: `
-kind: sources
-name: my-pg-instance
-type: cloud-sql-postgres
-project: my-project
-region: my-region
-instance: my-instance
-database: my_db
-user: my_user
-password: my_pass
----
-kind: tools
-name: example_tool
-type: postgres-sql
-source: my-pg-instance
-description: some description
-statement: |
-    SELECT * FROM SQL_STATEMENT;
-parameters:
-- name: country
-  type: string
-  description: some description
----
-kind: toolsets
-name: example_toolset
-tools:
-- example_tool`,
-			want: `
-kind: sources
-name: my-pg-instance
-type: cloud-sql-postgres
-project: my-project
-region: my-region
-instance: my-instance
-database: my_db
-user: my_user
-password: my_pass
----
-kind: tools
-name: example_tool
-type: postgres-sql
-source: my-pg-instance
-description: some description
-statement: |
-    SELECT * FROM SQL_STATEMENT;
-parameters:
-- name: country
-  type: string
-  description: some description
----
-kind: toolsets
-name: example_toolset
-tools:
-- example_tool`,
-		},
-		{
-			desc:   "invalid source",
-			in:     `sources: invalid`,
-			isErr:  true,
-			errStr: "'sources' is not a map",
-		},
-		{
-			desc:   "invalid toolset",
-			in:     `toolsets: invalid`,
-			isErr:  true,
-			errStr: "'toolsets' is not a map",
-		},
-	}
-	for _, tc := range tcs {
-		t.Run(tc.desc, func(t *testing.T) {
-			output, err := convertToolsFile(ctx, []byte(tc.in))
-			if tc.isErr {
-				if err == nil {
-					t.Fatalf("missing error: %s", tc.errStr)
-				}
-				if err.Error() != tc.errStr {
-					t.Fatalf("invalid error string: got %s, want %s", err, tc.errStr)
-				}
-				return
-			}
-			if err != nil {
-				t.Fatalf("unexpected error: %s", err)
-			}
-
-			var docs1, docs2 []yaml.MapSlice
-			if docs1, err = decodeToMapSlice(string(output)); err != nil {
-				t.Fatalf("error decoding output: %s", err)
-			}
-			if docs2, err = decodeToMapSlice(tc.want); err != nil {
-				t.Fatalf("Error decoding want: %s", err)
-			}
-			if !reflect.DeepEqual(docs1, docs2) {
-				t.Fatalf("incorrect output: got %s, want %s", string(output), tc.want)
-			}
-		})
-	}
-}
-
-func decodeToMapSlice(data string) ([]yaml.MapSlice, error) {
-	// ensures that the order is correct
-	var docs []yaml.MapSlice
-	decoder := yaml.NewDecoder(strings.NewReader(data))
-	for {
-		var doc yaml.MapSlice
-		err := decoder.Decode(&doc)
-		if err == io.EOF {
-			break
-		}
-		if err != nil {
-			return nil, err
-		}
-		docs = append(docs, doc)
-	}
-	return docs, nil
-}
-
 func TestParseToolFile(t *testing.T) {
 	ctx, err := testutils.ContextWithNewLogger()
 	if err != nil {
@@ -810,7 +505,7 @@ func TestParseToolFile(t *testing.T) {
 		wantToolsFile ToolsFile
 	}{
 		{
-			description: "basic example tools file v1",
+			description: "basic example",
 			in: `
 			sources:
 				my-pg-instance:
@@ -840,7 +535,7 @@ func TestParseToolFile(t *testing.T) {
 				Sources: server.SourceConfigs{
 					"my-pg-instance": cloudsqlpgsrc.Config{
 						Name:     "my-pg-instance",
-						Type:     cloudsqlpgsrc.SourceType,
+						Kind:     cloudsqlpgsrc.SourceKind,
 						Project:  "my-project",
 						Region:   "my-region",
 						Instance: "my-instance",
@@ -853,7 +548,7 @@ func TestParseToolFile(t *testing.T) {
 				Tools: server.ToolConfigs{
 					"example_tool": postgressql.Config{
 						Name:        "example_tool",
-						Type:        "postgres-sql",
+						Kind:        "postgres-sql",
 						Source:      "my-pg-instance",
 						Description: "some description",
 						Statement:   "SELECT * FROM SQL_STATEMENT;\n",
@@ -873,121 +568,7 @@ func TestParseToolFile(t *testing.T) {
 			},
 		},
 		{
-			description: "basic example tools file v2",
-			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
----
-			kind: authServices
-			name: my-google-auth
-			type: google
-			clientId: testing-id
----
-			kind: embeddingModels
-			name: gemini-model
-			type: gemini
-			model: gemini-embedding-001
-			apiKey: some-key
-			dimension: 768
----
-			kind: tools
-			name: example_tool
-			type: postgres-sql
-			source: my-pg-instance
-			description: some description
-			statement: |
-				SELECT * FROM SQL_STATEMENT;
-			parameters:
-			- name: country
-			  type: string
-			  description: some description
----
-			kind: toolsets
-			name: example_toolset
-			tools:
-			- example_tool
----
-			kind: prompts
-			name: code_review
-			description: ask llm to analyze code quality
-			messages:
-			- content: "please review the following code for quality: {{.code}}"
-			arguments:
-			- name: code
-			  description: the code to review
-			`,
-			wantToolsFile: ToolsFile{
-				Sources: server.SourceConfigs{
-					"my-pg-instance": cloudsqlpgsrc.Config{
-						Name:     "my-pg-instance",
-						Type:     cloudsqlpgsrc.SourceType,
-						Project:  "my-project",
-						Region:   "my-region",
-						Instance: "my-instance",
-						IPType:   "public",
-						Database: "my_db",
-						User:     "my_user",
-						Password: "my_pass",
-					},
-				},
-				AuthServices: server.AuthServiceConfigs{
-					"my-google-auth": google.Config{
-						Name:     "my-google-auth",
-						Type:     google.AuthServiceType,
-						ClientID: "testing-id",
-					},
-				},
-				EmbeddingModels: server.EmbeddingModelConfigs{
-					"gemini-model": gemini.Config{
-						Name:      "gemini-model",
-						Type:      gemini.EmbeddingModelType,
-						Model:     "gemini-embedding-001",
-						ApiKey:    "some-key",
-						Dimension: 768,
-					},
-				},
-				Tools: server.ToolConfigs{
-					"example_tool": postgressql.Config{
-						Name:        "example_tool",
-						Type:        "postgres-sql",
-						Source:      "my-pg-instance",
-						Description: "some description",
-						Statement:   "SELECT * FROM SQL_STATEMENT;\n",
-						Parameters: []parameters.Parameter{
-							parameters.NewStringParameter("country", "some description"),
-						},
-						AuthRequired: []string{},
-					},
-				},
-				Toolsets: server.ToolsetConfigs{
-					"example_toolset": tools.ToolsetConfig{
-						Name:      "example_toolset",
-						ToolNames: []string{"example_tool"},
-					},
-				},
-				Prompts: server.PromptConfigs{
-					"code_review": custom.Config{
-						Name:        "code_review",
-						Description: "ask llm to analyze code quality",
-						Arguments: prompts.Arguments{
-							{Parameter: parameters.NewStringParameter("code", "the code to review")},
-						},
-						Messages: []prompts.Message{
-							{Role: "user", Content: "please review the following code for quality: {{.code}}"},
-						},
-					},
-				},
-			},
-		},
-		{
-			description: "only prompts",
+			description: "with prompts example",
 			in: `
             prompts:
                 my-prompt:
@@ -1108,7 +689,7 @@ func TestParseToolFileWithAuth(t *testing.T) {
 				Sources: server.SourceConfigs{
 					"my-pg-instance": cloudsqlpgsrc.Config{
 						Name:     "my-pg-instance",
-						Type:     cloudsqlpgsrc.SourceType,
+						Kind:     cloudsqlpgsrc.SourceKind,
 						Project:  "my-project",
 						Region:   "my-region",
 						Instance: "my-instance",
@@ -1121,19 +702,19 @@ func TestParseToolFileWithAuth(t *testing.T) {
 				AuthServices: server.AuthServiceConfigs{
 					"my-google-service": google.Config{
 						Name:     "my-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "my-client-id",
 					},
 					"other-google-service": google.Config{
 						Name:     "other-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "other-client-id",
 					},
 				},
 				Tools: server.ToolConfigs{
 					"example_tool": postgressql.Config{
 						Name:         "example_tool",
-						Type:         "postgres-sql",
+						Kind:         "postgres-sql",
 						Source:       "my-pg-instance",
 						Description:  "some description",
 						Statement:    "SELECT * FROM SQL_STATEMENT;\n",
@@ -1208,7 +789,7 @@ func TestParseToolFileWithAuth(t *testing.T) {
 				Sources: server.SourceConfigs{
 					"my-pg-instance": cloudsqlpgsrc.Config{
 						Name:     "my-pg-instance",
-						Type:     cloudsqlpgsrc.SourceType,
+						Kind:     cloudsqlpgsrc.SourceKind,
 						Project:  "my-project",
 						Region:   "my-region",
 						Instance: "my-instance",
@@ -1218,22 +799,22 @@ func TestParseToolFileWithAuth(t *testing.T) {
 						Password: "my_pass",
 					},
 				},
-				AuthServices: server.AuthServiceConfigs{
+				AuthSources: server.AuthServiceConfigs{
 					"my-google-service": google.Config{
 						Name:     "my-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "my-client-id",
 					},
 					"other-google-service": google.Config{
 						Name:     "other-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "other-client-id",
 					},
 				},
 				Tools: server.ToolConfigs{
 					"example_tool": postgressql.Config{
 						Name:         "example_tool",
-						Type:         "postgres-sql",
+						Kind:         "postgres-sql",
 						Source:       "my-pg-instance",
 						Description:  "some description",
 						Statement:    "SELECT * FROM SQL_STATEMENT;\n",
@@ -1310,7 +891,7 @@ func TestParseToolFileWithAuth(t *testing.T) {
 				Sources: server.SourceConfigs{
 					"my-pg-instance": cloudsqlpgsrc.Config{
 						Name:     "my-pg-instance",
-						Type:     cloudsqlpgsrc.SourceType,
+						Kind:     cloudsqlpgsrc.SourceKind,
 						Project:  "my-project",
 						Region:   "my-region",
 						Instance: "my-instance",
@@ -1323,19 +904,19 @@ func TestParseToolFileWithAuth(t *testing.T) {
 				AuthServices: server.AuthServiceConfigs{
 					"my-google-service": google.Config{
 						Name:     "my-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "my-client-id",
 					},
 					"other-google-service": google.Config{
 						Name:     "other-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "other-client-id",
 					},
 				},
 				Tools: server.ToolConfigs{
 					"example_tool": postgressql.Config{
 						Name:         "example_tool",
-						Type:         "postgres-sql",
+						Kind:         "postgres-sql",
 						Source:       "my-pg-instance",
 						Description:  "some description",
 						Statement:    "SELECT * FROM SQL_STATEMENT;\n",
@@ -1481,7 +1062,7 @@ func TestEnvVarReplacement(t *testing.T) {
 				Sources: server.SourceConfigs{
 					"my-http-instance": httpsrc.Config{
 						Name:           "my-http-instance",
-						Type:           httpsrc.SourceType,
+						Kind:           httpsrc.SourceKind,
 						BaseURL:        "http://test_server/",
 						Timeout:        "10s",
 						DefaultHeaders: map[string]string{"Authorization": "ACTUAL_HEADER"},
@@ -1491,19 +1072,19 @@ func TestEnvVarReplacement(t *testing.T) {
 				AuthServices: server.AuthServiceConfigs{
 					"my-google-service": google.Config{
 						Name:     "my-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "ACTUAL_CLIENT_ID",
 					},
 					"other-google-service": google.Config{
 						Name:     "other-google-service",
-						Type:     google.AuthServiceType,
+						Kind:     google.AuthServiceKind,
 						ClientID: "ACTUAL_CLIENT_ID_2",
 					},
 				},
 				Tools: server.ToolConfigs{
 					"example_tool": http.Config{
 						Name:         "example_tool",
-						Type:         "http",
+						Kind:         "http",
 						Source:       "my-instance",
 						Method:       "GET",
 						Path:         "search?name=alice&pet=cat",
@@ -1912,7 +1493,7 @@ func TestPrebuiltTools(t *testing.T) {
 			wantToolset: server.ToolsetConfigs{
 				"cloud_sql_postgres_admin_tools": tools.ToolsetConfig{
 					Name:      "cloud_sql_postgres_admin_tools",
-					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "postgres_upgrade_precheck", "clone_instance", "create_backup"},
+					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "postgres_upgrade_precheck", "clone_instance", "create_backup", "restore_backup"},
 				},
 			},
 		},
@@ -1922,7 +1503,7 @@ func TestPrebuiltTools(t *testing.T) {
 			wantToolset: server.ToolsetConfigs{
 				"cloud_sql_mysql_admin_tools": tools.ToolsetConfig{
 					Name:      "cloud_sql_mysql_admin_tools",
-					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "clone_instance", "create_backup"},
+					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "clone_instance", "create_backup", "restore_backup"},
 				},
 			},
 		},
@@ -1932,7 +1513,7 @@ func TestPrebuiltTools(t *testing.T) {
 			wantToolset: server.ToolsetConfigs{
 				"cloud_sql_mssql_admin_tools": tools.ToolsetConfig{
 					Name:      "cloud_sql_mssql_admin_tools",
-					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "clone_instance", "create_backup"},
+					ToolNames: []string{"create_instance", "get_instance", "list_instances", "create_database", "list_databases", "create_user", "wait_for_operation", "clone_instance", "create_backup", "restore_backup"},
 				},
 			},
 		},

docs/en/how-to/connect-ide/cloud_sql_mssql_admin_mcp.md

@@ -54,6 +54,7 @@ instance, database and users:
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 
 ## Install MCP Toolbox
 
@@ -301,6 +302,7 @@ instances and interacting with your database:
 * **wait_for_operation**: Waits for a Cloud SQL operation to complete.
 * **clone_instance**: Creates a clone of an existing Cloud SQL for SQL Server instance.
 * **create_backup**: Creates a backup on a Cloud SQL instance.
+* **restore_backup**: Restores a backup of a Cloud SQL instance.
 
 {{< notice note >}}
 Prebuilt tools are pre-1.0, so expect some tool changes between versions. LLMs

docs/en/how-to/connect-ide/cloud_sql_mysql_admin_mcp.md

@@ -54,6 +54,7 @@ database and users:
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 
 ## Install MCP Toolbox
 
@@ -301,6 +302,7 @@ instances and interacting with your database:
 * **wait_for_operation**: Waits for a Cloud SQL operation to complete.
 * **clone_instance**: Creates a clone of an existing Cloud SQL for MySQL instance.
 * **create_backup**: Creates a backup on a Cloud SQL instance.
+* **restore_backup**: Restores a backup of a Cloud SQL instance.
 
 {{< notice note >}}
 Prebuilt tools are pre-1.0, so expect some tool changes between versions. LLMs

docs/en/how-to/connect-ide/cloud_sql_pg_admin_mcp.md

@@ -54,6 +54,7 @@ instance, database and users:
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 
 ## Install MCP Toolbox
 
@@ -301,6 +302,7 @@ instances and interacting with your database:
 * **wait_for_operation**: Waits for a Cloud SQL operation to complete.
 * **clone_instance**: Creates a clone of an existing Cloud SQL for PostgreSQL instance.
 * **create_backup**: Creates a backup on a Cloud SQL instance.
+* **restore_backup**: Restores a backup of a Cloud SQL instance.
 
 {{< notice note >}}
 Prebuilt tools are pre-1.0, so expect some tool changes between versions. LLMs

docs/en/how-to/connect_via_mcp.md

@@ -20,6 +20,7 @@ The native SDKs can be combined with MCP clients in many cases.
 
 Toolbox currently supports the following versions of MCP specification:
 
+* [2025-11-25](https://modelcontextprotocol.io/specification/2025-11-25)
 * [2025-06-18](https://modelcontextprotocol.io/specification/2025-06-18)
 * [2025-03-26](https://modelcontextprotocol.io/specification/2025-03-26)
 * [2024-11-05](https://modelcontextprotocol.io/specification/2024-11-05)

docs/en/reference/prebuilt-tools.md

@@ -194,6 +194,7 @@ See [Usage Examples](../reference/cli.md#examples).
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 
 *   **Tools:**
     *   `create_instance`: Creates a new Cloud SQL for MySQL instance.
@@ -205,6 +206,7 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `wait_for_operation`: Waits for a Cloud SQL operation to complete.
     *   `clone_instance`: Creates a clone for an existing Cloud SQL for MySQL instance.
     *   `create_backup`: Creates a backup on a Cloud SQL instance.
+    *   `restore_backup`: Restores a backup of a Cloud SQL instance.
 
 ## Cloud SQL for PostgreSQL
 
@@ -284,6 +286,7 @@ See [Usage Examples](../reference/cli.md#examples).
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 *   **Tools:**
     *   `create_instance`: Creates a new Cloud SQL for PostgreSQL instance.
     *   `get_instance`: Gets information about a Cloud SQL instance.
@@ -294,6 +297,7 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `wait_for_operation`: Waits for a Cloud SQL operation to complete.
     *   `clone_instance`: Creates a clone for an existing Cloud SQL for PostgreSQL instance.
     *   `create_backup`: Creates a backup on a Cloud SQL instance.
+    *   `restore_backup`: Restores a backup of a Cloud SQL instance.
 
 ## Cloud SQL for SQL Server
 
@@ -347,6 +351,7 @@ See [Usage Examples](../reference/cli.md#examples).
         * `create_instance`
         * `create_user`
         * `clone_instance`
+        * `restore_backup`
 *   **Tools:**
     *   `create_instance`: Creates a new Cloud SQL for SQL Server instance.
     *   `get_instance`: Gets information about a Cloud SQL instance.
@@ -357,6 +362,7 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `wait_for_operation`: Waits for a Cloud SQL operation to complete.
     *   `clone_instance`: Creates a clone for an existing Cloud SQL for SQL Server instance.
     *   `create_backup`: Creates a backup on a Cloud SQL instance.
+    *   `restore_backup`: Restores a backup of a Cloud SQL instance.
 
 ## Dataplex
 

docs/en/resources/tools/cloudgda/cloud-gda-query.md

@@ -41,13 +41,13 @@ tools:
 
 ### Usage Flow
 
-When using this tool, a `prompt` parameter containing a natural language query is provided to the tool (typically by an agent). The tool then interacts with the Gemini Data Analytics API using the context defined in your configuration.
+When using this tool, a `query` parameter containing a natural language query is provided to the tool (typically by an agent). The tool then interacts with the Gemini Data Analytics API using the context defined in your configuration.
 
 The structure of the response depends on the `generationOptions` configured in your tool definition (e.g., enabling `generateQueryResult` will include the SQL query results).
 
 See [Data Analytics API REST documentation](https://clouddocs.devsite.corp.google.com/gemini/docs/conversational-analytics-api/reference/rest/v1alpha/projects.locations/queryData?rep_location=global) for details.
 
-**Example Input Prompt:**
+**Example Input Query:**
 
 ```text
 How many accounts who have region in Prague are eligible for loans? A3 contains the data of region.

docs/en/resources/tools/cloudsql/cloudsqlrestorebackup.md

@@ -0,0 +1,53 @@
+---
+title: cloud-sql-restore-backup
+type: docs
+weight: 10
+description: "Restores a backup of a Cloud SQL instance."
+---
+
+The `cloud-sql-restore-backup` tool restores a backup on a Cloud SQL instance using the Cloud SQL Admin API.
+
+{{< notice info dd>}}
+This tool uses a `source` of kind `cloud-sql-admin`.
+{{< /notice >}}
+
+## Examples
+
+Basic backup restore
+
+```yaml
+tools:
+  backup-restore-basic:
+    kind: cloud-sql-restore-backup
+    source: cloud-sql-admin-source
+    description: "Restores a backup onto the given Cloud SQL instance."
+```
+
+## Reference
+
+### Tool Configuration
+| **field**      | **type** | **required** | **description**                                  |
+| -------------- | :------: | :----------: | ------------------------------------------------ |
+| kind           | string   | true         | Must be "cloud-sql-restore-backup".              |
+| source         | string   | true         | The name of the `cloud-sql-admin` source to use. |
+| description    | string   | false        | A description of the tool.                       |
+
+### Tool Inputs
+
+| **parameter**     | **type** | **required** | **description**                                                              |
+| ------------------| :------: | :----------: | -----------------------------------------------------------------------------|
+| target_project    | string   | true         | The project ID of the instance to restore the backup onto.                   |
+| target_instance   | string   | true         | The instance to restore the backup onto. Does not include the project ID.    |
+| backup_id         | string   | true         | The identifier of the backup being restored.                                 |
+| source_project    | string   | false        | (Optional) The project ID of the instance that the backup belongs to.        |
+| source_instance   | string   | false        | (Optional) Cloud SQL instance ID of the instance that the backup belongs to. |
+
+## Usage Notes
+
+- The `backup_id` field can be a BackupRun ID (which will be an int64), backup name, or BackupDR backup name.
+- If the `backup_id` field contains a BackupRun ID (i.e. an int64), the optional fields `source_project` and `source_instance` must also be provided.
+
+## See Also
+- [Cloud SQL Admin API documentation](https://cloud.google.com/sql/docs/mysql/admin-api)
+- [Toolbox Cloud SQL tools documentation](../cloudsql)
+- [Cloud SQL Restore API documentation](https://cloud.google.com/sql/docs/mysql/backup-recovery/restoring)

internal/auth/auth.go

@@ -21,13 +21,13 @@ import (
 
 // AuthServiceConfig is the interface for configuring authentication services.
 type AuthServiceConfig interface {
-	AuthServiceConfigType() string
+	AuthServiceConfigKind() string
 	Initialize() (AuthService, error)
 }
 
 // AuthService is the interface for authentication services.
 type AuthService interface {
-	AuthServiceType() string
+	AuthServiceKind() string
 	GetName() string
 	GetClaimsFromHeader(context.Context, http.Header) (map[string]any, error)
 	ToConfig() AuthServiceConfig

internal/auth/google/google.go

@@ -23,7 +23,7 @@ import (
 	"google.golang.org/api/idtoken"
 )
 
-const AuthServiceType string = "google"
+const AuthServiceKind string = "google"
 
 // validate interface
 var _ auth.AuthServiceConfig = Config{}
@@ -31,13 +31,13 @@ var _ auth.AuthServiceConfig = Config{}
 // Auth service configuration
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	ClientID string `yaml:"clientId" validate:"required"`
 }
 
-// Returns the auth service type
-func (cfg Config) AuthServiceConfigType() string {
-	return AuthServiceType
+// Returns the auth service kind
+func (cfg Config) AuthServiceConfigKind() string {
+	return AuthServiceKind
 }
 
 // Initialize a Google auth service
@@ -55,9 +55,9 @@ type AuthService struct {
 	Config
 }
 
-// Returns the auth service type
-func (a AuthService) AuthServiceType() string {
-	return AuthServiceType
+// Returns the auth service kind
+func (a AuthService) AuthServiceKind() string {
+	return AuthServiceKind
 }
 
 func (a AuthService) ToConfig() auth.AuthServiceConfig {

internal/embeddingmodels/embeddingmodels.go

@@ -22,12 +22,12 @@ import (
 
 // EmbeddingModelConfig is the interface for configuring embedding models.
 type EmbeddingModelConfig interface {
-	EmbeddingModelConfigType() string
+	EmbeddingModelConfigKind() string
 	Initialize(context.Context) (EmbeddingModel, error)
 }
 
 type EmbeddingModel interface {
-	EmbeddingModelType() string
+	EmbeddingModelKind() string
 	ToConfig() EmbeddingModelConfig
 	EmbedParameters(context.Context, []string) ([][]float32, error)
 }

internal/embeddingmodels/gemini/gemini.go

@@ -23,22 +23,22 @@ import (
 	"google.golang.org/genai"
 )
 
-const EmbeddingModelType string = "gemini"
+const EmbeddingModelKind string = "gemini"
 
 // validate interface
 var _ embeddingmodels.EmbeddingModelConfig = Config{}
 
 type Config struct {
 	Name      string `yaml:"name" validate:"required"`
-	Type      string `yaml:"type" validate:"required"`
+	Kind      string `yaml:"kind" validate:"required"`
 	Model     string `yaml:"model" validate:"required"`
 	ApiKey    string `yaml:"apiKey"`
 	Dimension int32  `yaml:"dimension"`
 }
 
-// Returns the embedding model type
-func (cfg Config) EmbeddingModelConfigType() string {
-	return EmbeddingModelType
+// Returns the embedding model kind
+func (cfg Config) EmbeddingModelConfigKind() string {
+	return EmbeddingModelKind
 }
 
 // Initialize a Gemini embedding model
@@ -69,9 +69,9 @@ type EmbeddingModel struct {
 	Config
 }
 
-// Returns the embedding model type
-func (m EmbeddingModel) EmbeddingModelType() string {
-	return EmbeddingModelType
+// Returns the embedding model kind
+func (m EmbeddingModel) EmbeddingModelKind() string {
+	return EmbeddingModelKind
 }
 
 func (m EmbeddingModel) ToConfig() embeddingmodels.EmbeddingModelConfig {

internal/embeddingmodels/gemini/gemini_test.go

@@ -15,9 +15,9 @@
 package gemini_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/embeddingmodels"
 	"github.com/googleapis/genai-toolbox/internal/embeddingmodels/gemini"
@@ -34,15 +34,15 @@ func TestParseFromYamlGemini(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: embeddingModels
-			name: my-gemini-model
-			type: gemini
-			model: text-embedding-004
+            embeddingModels:
+                my-gemini-model:
+                    kind: gemini
+                    model: text-embedding-004
             `,
 			want: map[string]embeddingmodels.EmbeddingModelConfig{
 				"my-gemini-model": gemini.Config{
 					Name:  "my-gemini-model",
-					Type:  gemini.EmbeddingModelType,
+					Kind:  gemini.EmbeddingModelKind,
 					Model: "text-embedding-004",
 				},
 			},
@@ -50,17 +50,17 @@ func TestParseFromYamlGemini(t *testing.T) {
 		{
 			desc: "full example with optional fields",
 			in: `
-            kind: embeddingModels
-            name: complex-gemini
-            type: gemini
-            model: text-embedding-004
-            apiKey: "test-api-key"
-            dimension: 768
+            embeddingModels:
+                complex-gemini:
+                    kind: gemini
+                    model: text-embedding-004
+                    apiKey: "test-api-key"
+                    dimension: 768
             `,
 			want: map[string]embeddingmodels.EmbeddingModelConfig{
 				"complex-gemini": gemini.Config{
 					Name:      "complex-gemini",
-					Type:      gemini.EmbeddingModelType,
+					Kind:      gemini.EmbeddingModelKind,
 					Model:     "text-embedding-004",
 					ApiKey:    "test-api-key",
 					Dimension: 768,
@@ -70,13 +70,16 @@ func TestParseFromYamlGemini(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Models server.EmbeddingModelConfigs `yaml:"embeddingModels"`
+			}{}
 			// Parse contents
-			_, _, got, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: %v", cmp.Diff(tc.want, got))
+			if !cmp.Equal(tc.want, got.Models) {
+				t.Fatalf("incorrect parse: %v", cmp.Diff(tc.want, got.Models))
 			}
 		})
 	}
@@ -90,29 +93,32 @@ func TestFailParseFromYamlGemini(t *testing.T) {
 		{
 			desc: "missing required model field",
 			in: `
-            kind: embeddingModels
-            name: bad-model
-            type: gemini
+            embeddingModels:
+                bad-model:
+                    kind: gemini
             `,
 			// Removed the specific model name from the prefix to match your output
-			err: "error unmarshaling embeddingModels: unable to parse as \"bad-model\": Key: 'Config.Model' Error:Field validation for 'Model' failed on the 'required' tag",
+			err: "unable to parse as \"gemini\": Key: 'Config.Model' Error:Field validation for 'Model' failed on the 'required' tag",
 		},
 		{
 			desc: "unknown field",
 			in: `
-            kind: embeddingModels
-            name: bad-field
-            type: gemini
-            model: text-embedding-004
-            invalid_param: true
+            embeddingModels:
+                bad-field:
+                    kind: gemini
+                    model: text-embedding-004
+                    invalid_param: true
             `,
 			// Updated to match the specific line-starting format of your error output
-			err: "error unmarshaling embeddingModels: unable to parse as \"bad-field\": [1:1] unknown field \"invalid_param\"\n>  1 | invalid_param: true\n       ^\n   2 | model: text-embedding-004\n   3 | name: bad-field\n   4 | type: gemini",
+			err: "unable to parse as \"gemini\": [1:1] unknown field \"invalid_param\"\n>  1 | invalid_param: true\n       ^\n   2 | kind: gemini\n   3 | model: text-embedding-004",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Models server.EmbeddingModelConfigs `yaml:"embeddingModels"`
+			}{}
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/prebuiltconfigs/tools/cloud-sql-mssql-admin.yaml

@@ -46,6 +46,9 @@ tools:
   create_backup:
     kind: cloud-sql-create-backup
     source: cloud-sql-admin-source
+  restore_backup:
+    kind: cloud-sql-restore-backup
+    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_mssql_admin_tools:
@@ -58,3 +61,4 @@ toolsets:
     - wait_for_operation
     - clone_instance
     - create_backup
+    - restore_backup

internal/prebuiltconfigs/tools/cloud-sql-mysql-admin.yaml

@@ -46,6 +46,9 @@ tools:
   create_backup:
     kind: cloud-sql-create-backup
     source: cloud-sql-admin-source
+  restore_backup:
+    kind: cloud-sql-restore-backup
+    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_mysql_admin_tools:
@@ -58,3 +61,4 @@ toolsets:
     - wait_for_operation
     - clone_instance
     - create_backup
+    - restore_backup

internal/prebuiltconfigs/tools/cloud-sql-postgres-admin.yaml

@@ -49,6 +49,9 @@ tools:
   create_backup:
     kind: cloud-sql-create-backup
     source: cloud-sql-admin-source
+  restore_backup:
+    kind: cloud-sql-restore-backup
+    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_postgres_admin_tools:
@@ -62,3 +65,4 @@ toolsets:
     - postgres_upgrade_precheck
     - clone_instance
     - create_backup
+    - restore_backup

internal/prompts/custom/custom.go

@@ -25,12 +25,12 @@ import (
 
 type Message = prompts.Message
 
-const resourceType = "custom"
+const kind = "custom"
 
-// init registers this prompt type with the prompt framework.
+// init registers this prompt kind with the prompt framework.
 func init() {
-	if !prompts.Register(resourceType, newConfig) {
-		panic(fmt.Sprintf("prompt type %q already registered", resourceType))
+	if !prompts.Register(kind, newConfig) {
+		panic(fmt.Sprintf("prompt kind %q already registered", kind))
 	}
 }
 
@@ -56,8 +56,8 @@ type Config struct {
 var _ prompts.PromptConfig = Config{}
 var _ prompts.Prompt = Prompt{}
 
-func (c Config) PromptConfigType() string {
-	return resourceType
+func (c Config) PromptConfigKind() string {
+	return kind
 }
 
 func (c Config) Initialize() (prompts.Prompt, error) {

internal/prompts/custom/custom_test.go

@@ -42,7 +42,7 @@ func TestConfig(t *testing.T) {
 		Arguments: testArgs,
 	}
 
-	// initialize and check type
+	// initialize and check kind
 	p, err := cfg.Initialize()
 	if err != nil {
 		t.Fatalf("Initialize() failed: %v", err)
@@ -50,8 +50,8 @@ func TestConfig(t *testing.T) {
 	if p == nil {
 		t.Fatal("Initialize() returned a nil prompt")
 	}
-	if cfg.PromptConfigType() != "custom" {
-		t.Errorf("PromptConfigType() = %q, want %q", cfg.PromptConfigType(), "custom")
+	if cfg.PromptConfigKind() != "custom" {
+		t.Errorf("PromptConfigKind() = %q, want %q", cfg.PromptConfigKind(), "custom")
 	}
 
 	t.Run("Manifest", func(t *testing.T) {

internal/prompts/prompts.go

@@ -30,40 +30,40 @@ var promptRegistry = make(map[string]PromptConfigFactory)
 
 // Register allows individual prompt packages to register their configuration
 // factory function. This is typically called from an init() function in the
-// prompt's package. It associates a 'type' string with a function that can
+// prompt's package. It associates a 'kind' string with a function that can
 // produce the specific PromptConfig type. It returns true if the registration was
-// successful, and false if a prompt with the same type was already registered.
-func Register(resourceType string, factory PromptConfigFactory) bool {
-	if _, exists := promptRegistry[resourceType]; exists {
-		// Prompt with this type already exists, do not overwrite.
+// successful, and false if a prompt with the same kind was already registered.
+func Register(kind string, factory PromptConfigFactory) bool {
+	if _, exists := promptRegistry[kind]; exists {
+		// Prompt with this kind already exists, do not overwrite.
 		return false
 	}
-	promptRegistry[resourceType] = factory
+	promptRegistry[kind] = factory
 	return true
 }
 
-// DecodeConfig looks up the registered factory for the given type and uses it
+// DecodeConfig looks up the registered factory for the given kind and uses it
 // to decode the prompt configuration.
-func DecodeConfig(ctx context.Context, resourceType, name string, decoder *yaml.Decoder) (PromptConfig, error) {
-	factory, found := promptRegistry[resourceType]
-	if !found && resourceType == "" {
-		resourceType = "custom"
-		factory, found = promptRegistry[resourceType]
+func DecodeConfig(ctx context.Context, kind, name string, decoder *yaml.Decoder) (PromptConfig, error) {
+	factory, found := promptRegistry[kind]
+	if !found && kind == "" {
+		kind = "custom"
+		factory, found = promptRegistry[kind]
 	}
 
 	if !found {
-		return nil, fmt.Errorf("unknown prompt type: %q", resourceType)
+		return nil, fmt.Errorf("unknown prompt kind: %q", kind)
 	}
 
 	promptConfig, err := factory(ctx, name, decoder)
 	if err != nil {
-		return nil, fmt.Errorf("unable to parse prompt %q as resourceType %q: %w", name, resourceType, err)
+		return nil, fmt.Errorf("unable to parse prompt %q as kind %q: %w", name, kind, err)
 	}
 	return promptConfig, nil
 }
 
 type PromptConfig interface {
-	PromptConfigType() string
+	PromptConfigKind() string
 	Initialize() (Prompt, error)
 }
 

internal/prompts/prompts_test.go

@@ -29,16 +29,16 @@ import (
 
 type mockPromptConfig struct {
 	name string
-	Type string
+	kind string
 }
 
-func (m *mockPromptConfig) PromptConfigType() string            { return m.Type }
+func (m *mockPromptConfig) PromptConfigKind() string            { return m.kind }
 func (m *mockPromptConfig) Initialize() (prompts.Prompt, error) { return nil, nil }
 
 var errMockFactory = errors.New("mock factory error")
 
 func mockFactory(ctx context.Context, name string, decoder *yaml.Decoder) (prompts.PromptConfig, error) {
-	return &mockPromptConfig{name: name, Type: "mockType"}, nil
+	return &mockPromptConfig{name: name, kind: "mockKind"}, nil
 }
 
 func mockErrorFactory(ctx context.Context, name string, decoder *yaml.Decoder) (prompts.PromptConfig, error) {
@@ -50,17 +50,17 @@ func TestRegistry(t *testing.T) {
 	ctx := context.Background()
 
 	t.Run("RegisterAndDecodeSuccess", func(t *testing.T) {
-		resourceType := "testTypeSuccess"
-		if !prompts.Register(resourceType, mockFactory) {
+		kind := "testKindSuccess"
+		if !prompts.Register(kind, mockFactory) {
 			t.Fatal("expected registration to succeed")
 		}
 		// This should fail because we are registering a duplicate
-		if prompts.Register(resourceType, mockFactory) {
+		if prompts.Register(kind, mockFactory) {
 			t.Fatal("expected duplicate registration to fail")
 		}
 
 		decoder := yaml.NewDecoder(strings.NewReader(""))
-		config, err := prompts.DecodeConfig(ctx, resourceType, "testPrompt", decoder)
+		config, err := prompts.DecodeConfig(ctx, kind, "testPrompt", decoder)
 		if err != nil {
 			t.Fatalf("expected DecodeConfig to succeed, but got error: %v", err)
 		}
@@ -69,25 +69,25 @@ func TestRegistry(t *testing.T) {
 		}
 	})
 
-	t.Run("DecodeUnknownType", func(t *testing.T) {
+	t.Run("DecodeUnknownKind", func(t *testing.T) {
 		decoder := yaml.NewDecoder(strings.NewReader(""))
-		_, err := prompts.DecodeConfig(ctx, "unregisteredType", "testPrompt", decoder)
+		_, err := prompts.DecodeConfig(ctx, "unregisteredKind", "testPrompt", decoder)
 		if err == nil {
-			t.Fatal("expected an error for unknown type, but got nil")
+			t.Fatal("expected an error for unknown kind, but got nil")
 		}
-		if !strings.Contains(err.Error(), "unknown prompt type") {
-			t.Errorf("expected error to contain 'unknown prompt type', but got: %v", err)
+		if !strings.Contains(err.Error(), "unknown prompt kind") {
+			t.Errorf("expected error to contain 'unknown prompt kind', but got: %v", err)
 		}
 	})
 
 	t.Run("FactoryReturnsError", func(t *testing.T) {
-		resourceType := "testTypeError"
-		if !prompts.Register(resourceType, mockErrorFactory) {
+		kind := "testKindError"
+		if !prompts.Register(kind, mockErrorFactory) {
 			t.Fatal("expected registration to succeed")
 		}
 
 		decoder := yaml.NewDecoder(strings.NewReader(""))
-		_, err := prompts.DecodeConfig(ctx, resourceType, "testPrompt", decoder)
+		_, err := prompts.DecodeConfig(ctx, kind, "testPrompt", decoder)
 		if err == nil {
 			t.Fatal("expected an error from the factory, but got nil")
 		}
@@ -100,13 +100,13 @@ func TestRegistry(t *testing.T) {
 		decoder := yaml.NewDecoder(strings.NewReader("description: A test prompt"))
 		config, err := prompts.DecodeConfig(ctx, "", "testDefaultPrompt", decoder)
 		if err != nil {
-			t.Fatalf("expected DecodeConfig with empty type to succeed, but got error: %v", err)
+			t.Fatalf("expected DecodeConfig with empty kind to succeed, but got error: %v", err)
 		}
 		if config == nil {
-			t.Fatal("expected a non-nil config for default type")
+			t.Fatal("expected a non-nil config for default kind")
 		}
-		if config.PromptConfigType() != "custom" {
-			t.Errorf("expected default type to be 'custom', but got %q", config.PromptConfigType())
+		if config.PromptConfigKind() != "custom" {
+			t.Errorf("expected default kind to be 'custom', but got %q", config.PromptConfigKind())
 		}
 	})
 }

internal/server/config.go

@@ -14,10 +14,9 @@
 package server
 
 import (
-	"bytes"
 	"context"
 	"fmt"
-	"io"
+	"regexp"
 	"strings"
 
 	yaml "github.com/goccy/go-yaml"
@@ -126,201 +125,296 @@ func (s *StringLevel) Type() string {
 	return "stringLevel"
 }
 
+// SourceConfigs is a type used to allow unmarshal of the data source config map
 type SourceConfigs map[string]sources.SourceConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &SourceConfigs{}
+
+func (c *SourceConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(SourceConfigs)
+	// Parse the 'kind' fields for each source
+	var raw map[string]util.DelayedUnmarshaler
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, u := range raw {
+		// Unmarshal to a general type that ensure it capture all fields
+		var v map[string]any
+		if err := u.Unmarshal(&v); err != nil {
+			return fmt.Errorf("unable to unmarshal %q: %w", name, err)
+		}
+
+		kind, ok := v["kind"]
+		if !ok {
+			return fmt.Errorf("missing 'kind' field for source %q", name)
+		}
+		kindStr, ok := kind.(string)
+		if !ok {
+			return fmt.Errorf("invalid 'kind' field for source %q (must be a string)", name)
+		}
+
+		yamlDecoder, err := util.NewStrictDecoder(v)
+		if err != nil {
+			return fmt.Errorf("error creating YAML decoder for source %q: %w", name, err)
+		}
+
+		sourceConfig, err := sources.DecodeConfig(ctx, kindStr, name, yamlDecoder)
+		if err != nil {
+			return err
+		}
+		(*c)[name] = sourceConfig
+	}
+	return nil
+}
+
+// AuthServiceConfigs is a type used to allow unmarshal of the data authService config map
 type AuthServiceConfigs map[string]auth.AuthServiceConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &AuthServiceConfigs{}
+
+func (c *AuthServiceConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(AuthServiceConfigs)
+	// Parse the 'kind' fields for each authService
+	var raw map[string]util.DelayedUnmarshaler
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, u := range raw {
+		var v map[string]any
+		if err := u.Unmarshal(&v); err != nil {
+			return fmt.Errorf("unable to unmarshal %q: %w", name, err)
+		}
+
+		kind, ok := v["kind"]
+		if !ok {
+			return fmt.Errorf("missing 'kind' field for %q", name)
+		}
+
+		dec, err := util.NewStrictDecoder(v)
+		if err != nil {
+			return fmt.Errorf("error creating decoder: %w", err)
+		}
+		switch kind {
+		case google.AuthServiceKind:
+			actual := google.Config{Name: name}
+			if err := dec.DecodeContext(ctx, &actual); err != nil {
+				return fmt.Errorf("unable to parse as %q: %w", kind, err)
+			}
+			(*c)[name] = actual
+		default:
+			return fmt.Errorf("%q is not a valid kind of auth source", kind)
+		}
+	}
+	return nil
+}
+
+// EmbeddingModelConfigs is a type used to allow unmarshal of the embedding model config map
 type EmbeddingModelConfigs map[string]embeddingmodels.EmbeddingModelConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &EmbeddingModelConfigs{}
+
+func (c *EmbeddingModelConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(EmbeddingModelConfigs)
+	// Parse the 'kind' fields for each embedding model
+	var raw map[string]util.DelayedUnmarshaler
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, u := range raw {
+		// Unmarshal to a general type that ensure it capture all fields
+		var v map[string]any
+		if err := u.Unmarshal(&v); err != nil {
+			return fmt.Errorf("unable to unmarshal embedding model %q: %w", name, err)
+		}
+
+		kind, ok := v["kind"]
+		if !ok {
+			return fmt.Errorf("missing 'kind' field for embedding model %q", name)
+		}
+
+		dec, err := util.NewStrictDecoder(v)
+		if err != nil {
+			return fmt.Errorf("error creating decoder: %w", err)
+		}
+		switch kind {
+		case gemini.EmbeddingModelKind:
+			actual := gemini.Config{Name: name}
+			if err := dec.DecodeContext(ctx, &actual); err != nil {
+				return fmt.Errorf("unable to parse as %q: %w", kind, err)
+			}
+			(*c)[name] = actual
+		default:
+			return fmt.Errorf("%q is not a valid kind of auth source", kind)
+		}
+	}
+	return nil
+}
+
+// ToolConfigs is a type used to allow unmarshal of the tool configs
 type ToolConfigs map[string]tools.ToolConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &ToolConfigs{}
+
+func (c *ToolConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(ToolConfigs)
+	// Parse the 'kind' fields for each source
+	var raw map[string]util.DelayedUnmarshaler
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, u := range raw {
+		err := NameValidation(name)
+		if err != nil {
+			return err
+		}
+		var v map[string]any
+		if err := u.Unmarshal(&v); err != nil {
+			return fmt.Errorf("unable to unmarshal %q: %w", name, err)
+		}
+
+		// `authRequired` and `useClientOAuth` cannot be specified together
+		if v["authRequired"] != nil && v["useClientOAuth"] == true {
+			return fmt.Errorf("`authRequired` and `useClientOAuth` are mutually exclusive. Choose only one authentication method")
+		}
+
+		// Make `authRequired` an empty list instead of nil for Tool manifest
+		if v["authRequired"] == nil {
+			v["authRequired"] = []string{}
+		}
+
+		kindVal, ok := v["kind"]
+		if !ok {
+			return fmt.Errorf("missing 'kind' field for tool %q", name)
+		}
+		kindStr, ok := kindVal.(string)
+		if !ok {
+			return fmt.Errorf("invalid 'kind' field for tool %q (must be a string)", name)
+		}
+
+		yamlDecoder, err := util.NewStrictDecoder(v)
+		if err != nil {
+			return fmt.Errorf("error creating YAML decoder for tool %q: %w", name, err)
+		}
+
+		toolCfg, err := tools.DecodeConfig(ctx, kindStr, name, yamlDecoder)
+		if err != nil {
+			return err
+		}
+		(*c)[name] = toolCfg
+	}
+	return nil
+}
+
+// ToolsetConfigs is a type used to allow unmarshal of the toolset configs
 type ToolsetConfigs map[string]tools.ToolsetConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &ToolsetConfigs{}
+
+func (c *ToolsetConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(ToolsetConfigs)
+
+	var raw map[string][]string
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, toolList := range raw {
+		(*c)[name] = tools.ToolsetConfig{Name: name, ToolNames: toolList}
+	}
+	return nil
+}
+
+// PromptConfigs is a type used to allow unmarshal of the prompt configs
 type PromptConfigs map[string]prompts.PromptConfig
+
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &PromptConfigs{}
+
+func (c *PromptConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(PromptConfigs)
+	var raw map[string]util.DelayedUnmarshaler
+	if err := unmarshal(&raw); err != nil {
+		return err
+	}
+
+	for name, u := range raw {
+		var v map[string]any
+		if err := u.Unmarshal(&v); err != nil {
+			return fmt.Errorf("unable to unmarshal prompt %q: %w", name, err)
+		}
+
+		// Look for the 'kind' field. If it's not present, kindStr will be an
+		// empty string, which prompts.DecodeConfig will correctly default to "custom".
+		var kindStr string
+		if kindVal, ok := v["kind"]; ok {
+			var isString bool
+			kindStr, isString = kindVal.(string)
+			if !isString {
+				return fmt.Errorf("invalid 'kind' field for prompt %q (must be a string)", name)
+			}
+		}
+
+		// Create a new, strict decoder for this specific prompt's data.
+		yamlDecoder, err := util.NewStrictDecoder(v)
+		if err != nil {
+			return fmt.Errorf("error creating YAML decoder for prompt %q: %w", name, err)
+		}
+
+		// Use the central registry to decode the prompt based on its kind.
+		promptCfg, err := prompts.DecodeConfig(ctx, kindStr, name, yamlDecoder)
+		if err != nil {
+			return err
+		}
+		(*c)[name] = promptCfg
+	}
+	return nil
+}
+
+// PromptsetConfigs is a type used to allow unmarshal of the PromptsetConfigs configs
 type PromptsetConfigs map[string]prompts.PromptsetConfig
 
-func UnmarshalResourceConfig(ctx context.Context, raw []byte) (SourceConfigs, AuthServiceConfigs, EmbeddingModelConfigs, ToolConfigs, ToolsetConfigs, PromptConfigs, error) {
-	// prepare configs map
-	sourceConfigs := make(map[string]sources.SourceConfig)
-	authServiceConfigs := make(AuthServiceConfigs)
-	embeddingModelConfigs := make(EmbeddingModelConfigs)
-	toolConfigs := make(ToolConfigs)
-	toolsetConfigs := make(ToolsetConfigs)
-	promptConfigs := make(PromptConfigs)
-	// promptset configs is not yet supported
+// validate interface
+var _ yaml.InterfaceUnmarshalerContext = &PromptsetConfigs{}
 
-	decoder := yaml.NewDecoder(bytes.NewReader(raw))
-	// for loop to unmarshal documents with the `---` separator
-	for {
-		var resource map[string]any
-		if err := decoder.DecodeContext(ctx, &resource); err != nil {
-			if err == io.EOF {
-				break
-			}
-			return nil, nil, nil, nil, nil, nil, fmt.Errorf("unable to decode YAML document: %w", err)
-		}
-		var kind, name string
-		var ok bool
-		if kind, ok = resource["kind"].(string); !ok {
-			return nil, nil, nil, nil, nil, nil, fmt.Errorf("missing 'kind' field or it is not a string")
-		}
-		if name, ok = resource["name"].(string); !ok {
-			return nil, nil, nil, nil, nil, nil, fmt.Errorf("missing 'name' field or it is not a string")
-		}
-		// remove 'kind' from map for strict unmarshaling
-		delete(resource, "kind")
+func (c *PromptsetConfigs) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
+	*c = make(PromptsetConfigs)
 
-		switch kind {
-		case "sources":
-			c, err := UnmarshalYAMLSourceConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			sourceConfigs[name] = c
-		case "authServices":
-			c, err := UnmarshalYAMLAuthServiceConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			authServiceConfigs[name] = c
-		case "tools":
-			c, err := UnmarshalYAMLToolConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			toolConfigs[name] = c
-		case "toolsets":
-			c, err := UnmarshalYAMLToolsetConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			toolsetConfigs[name] = c
-		case "embeddingModels":
-			c, err := UnmarshalYAMLEmbeddingModelConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			embeddingModelConfigs[name] = c
-		case "prompts":
-			c, err := UnmarshalYAMLPromptConfig(ctx, name, resource)
-			if err != nil {
-				return nil, nil, nil, nil, nil, nil, fmt.Errorf("error unmarshaling %s: %s", kind, err)
-			}
-			promptConfigs[name] = c
-		default:
-			return nil, nil, nil, nil, nil, nil, fmt.Errorf("invalid kind %s", kind)
-		}
-	}
-	return sourceConfigs, authServiceConfigs, embeddingModelConfigs, toolConfigs, toolsetConfigs, promptConfigs, nil
-}
-
-func UnmarshalYAMLSourceConfig(ctx context.Context, name string, r map[string]any) (sources.SourceConfig, error) {
-	resourceType, ok := r["type"].(string)
-	if !ok {
-		return nil, fmt.Errorf("missing 'type' field or it is not a string")
-	}
-	dec, err := util.NewStrictDecoder(r)
-	if err != nil {
-		return nil, fmt.Errorf("error creating decoder: %w", err)
-	}
-	sourceConfig, err := sources.DecodeConfig(ctx, resourceType, name, dec)
-	if err != nil {
-		return nil, err
-	}
-	return sourceConfig, nil
-}
-
-func UnmarshalYAMLAuthServiceConfig(ctx context.Context, name string, r map[string]any) (auth.AuthServiceConfig, error) {
-	resourceType, ok := r["type"].(string)
-	if !ok {
-		return nil, fmt.Errorf("missing 'type' field or it is not a string")
-	}
-	if resourceType != google.AuthServiceType {
-		return nil, fmt.Errorf("%s is not a valid type of auth service", resourceType)
-	}
-	dec, err := util.NewStrictDecoder(r)
-	if err != nil {
-		return nil, fmt.Errorf("error creating decoder: %s", err)
-	}
-	actual := google.Config{Name: name}
-	if err := dec.DecodeContext(ctx, &actual); err != nil {
-		return nil, fmt.Errorf("unable to parse as %s: %w", name, err)
-	}
-	return actual, nil
-}
-
-func UnmarshalYAMLEmbeddingModelConfig(ctx context.Context, name string, r map[string]any) (embeddingmodels.EmbeddingModelConfig, error) {
-	resourceType, ok := r["type"].(string)
-	if !ok {
-		return nil, fmt.Errorf("missing 'type' field or it is not a string")
-	}
-	if resourceType != gemini.EmbeddingModelType {
-		return nil, fmt.Errorf("%s is not a valid type of embedding model", resourceType)
-	}
-	dec, err := util.NewStrictDecoder(r)
-	if err != nil {
-		return nil, fmt.Errorf("error creating decoder: %s", err)
-	}
-	actual := gemini.Config{Name: name}
-	if err := dec.DecodeContext(ctx, &actual); err != nil {
-		return nil, fmt.Errorf("unable to parse as %q: %w", name, err)
-	}
-	return actual, nil
-}
-
-func UnmarshalYAMLToolConfig(ctx context.Context, name string, r map[string]any) (tools.ToolConfig, error) {
-	resourceType, ok := r["type"].(string)
-	if !ok {
-		return nil, fmt.Errorf("missing 'type' field or it is not a string")
-	}
-	// `authRequired` and `useClientOAuth` cannot be specified together
-	if r["authRequired"] != nil && r["useClientOAuth"] == true {
-		return nil, fmt.Errorf("`authRequired` and `useClientOAuth` are mutually exclusive. Choose only one authentication method")
-	}
-	// Make `authRequired` an empty list instead of nil for Tool manifest
-	if r["authRequired"] == nil {
-		r["authRequired"] = []string{}
-	}
-	dec, err := util.NewStrictDecoder(r)
-	if err != nil {
-		return nil, fmt.Errorf("error creating decoder: %s", err)
-	}
-	toolCfg, err := tools.DecodeConfig(ctx, resourceType, name, dec)
-	if err != nil {
-		return nil, err
-	}
-	return toolCfg, nil
-}
-
-func UnmarshalYAMLToolsetConfig(ctx context.Context, name string, r map[string]any) (tools.ToolsetConfig, error) {
-	var toolsetConfig tools.ToolsetConfig
-	justTools := map[string]any{"tools": r["tools"]}
-	dec, err := util.NewStrictDecoder(justTools)
-	if err != nil {
-		return toolsetConfig, fmt.Errorf("error creating decoder: %s", err)
-	}
 	var raw map[string][]string
-	if err := dec.DecodeContext(ctx, &raw); err != nil {
-		return toolsetConfig, fmt.Errorf("unable to unmarshal tools: %s", err)
-	}
-	return tools.ToolsetConfig{Name: name, ToolNames: raw["tools"]}, nil
-}
-
-func UnmarshalYAMLPromptConfig(ctx context.Context, name string, r map[string]any) (prompts.PromptConfig, error) {
-	// Look for the 'type' field. If it's not present, typeStr will be an
-	// empty string, which prompts.DecodeConfig will correctly default to "custom".
-	var resourceType string
-	if typeVal, ok := r["type"]; ok {
-		var isString bool
-		resourceType, isString = typeVal.(string)
-		if !isString {
-			return nil, fmt.Errorf("invalid 'type' field for prompt %q (must be a string)", name)
-		}
-	}
-	dec, err := util.NewStrictDecoder(r)
-	if err != nil {
-		return nil, fmt.Errorf("error creating decoder: %s", err)
+	if err := unmarshal(&raw); err != nil {
+		return err
 	}
 
-	// Use the central registry to decode the prompt based on its type.
-	promptCfg, err := prompts.DecodeConfig(ctx, resourceType, name, dec)
-	if err != nil {
-		return nil, err
+	for name, promptList := range raw {
+		(*c)[name] = prompts.PromptsetConfig{Name: name, PromptNames: promptList}
 	}
-	return promptCfg, nil
+	return nil
+}
+
+// Tools naming validation is added in the MCP v2025-11-25, but we'll be
+// implementing it across Toolbox
+// Tool names SHOULD be between 1 and 128 characters in length (inclusive).
+// Tool names SHOULD be considered case-sensitive.
+// The following SHOULD be the only allowed characters: uppercase and lowercase ASCII letters (A-Z, a-z), digits (0-9), underscore (_), hyphen (-), and dot (.)
+// Tool names SHOULD NOT contain spaces, commas, or other special characters.
+// Tool names SHOULD be unique within a server.
+func NameValidation(name string) error {
+	strLen := len(name)
+	if strLen < 1 || strLen > 128 {
+		return fmt.Errorf("resource name SHOULD be between 1 and 128 characters in length (inclusive)")
+	}
+	validChars := regexp.MustCompile("^[a-zA-Z0-9_.-]+$")
+	isValid := validChars.MatchString(name)
+	if !isValid {
+		return fmt.Errorf("invalid character for resource name; only uppercase and lowercase ASCII letters (A-Z, a-z), digits (0-9), underscore (_), hyphen (-), and dot (.) is allowed")
+	}
+	return nil
 }

internal/server/mcp/mcp.go

@@ -27,19 +27,21 @@ import (
 	v20241105 "github.com/googleapis/genai-toolbox/internal/server/mcp/v20241105"
 	v20250326 "github.com/googleapis/genai-toolbox/internal/server/mcp/v20250326"
 	v20250618 "github.com/googleapis/genai-toolbox/internal/server/mcp/v20250618"
+	v20251125 "github.com/googleapis/genai-toolbox/internal/server/mcp/v20251125"
 	"github.com/googleapis/genai-toolbox/internal/server/resources"
 	"github.com/googleapis/genai-toolbox/internal/tools"
 )
 
 // LATEST_PROTOCOL_VERSION is the latest version of the MCP protocol supported.
 // Update the version used in InitializeResponse when this value is updated.
-const LATEST_PROTOCOL_VERSION = v20250618.PROTOCOL_VERSION
+const LATEST_PROTOCOL_VERSION = v20251125.PROTOCOL_VERSION
 
 // SUPPORTED_PROTOCOL_VERSIONS is the MCP protocol versions that are supported.
 var SUPPORTED_PROTOCOL_VERSIONS = []string{
 	v20241105.PROTOCOL_VERSION,
 	v20250326.PROTOCOL_VERSION,
 	v20250618.PROTOCOL_VERSION,
+	v20251125.PROTOCOL_VERSION,
 }
 
 // InitializeResponse runs capability negotiation and protocol version agreement.
@@ -102,6 +104,8 @@ func NotificationHandler(ctx context.Context, body []byte) error {
 // This is the Operation phase of the lifecycle for MCP client-server connections.
 func ProcessMethod(ctx context.Context, mcpVersion string, id jsonrpc.RequestId, method string, toolset tools.Toolset, promptset prompts.Promptset, resourceMgr *resources.ResourceManager, body []byte, header http.Header) (any, error) {
 	switch mcpVersion {
+	case v20251125.PROTOCOL_VERSION:
+		return v20251125.ProcessMethod(ctx, id, method, toolset, promptset, resourceMgr, body, header)
 	case v20250618.PROTOCOL_VERSION:
 		return v20250618.ProcessMethod(ctx, id, method, toolset, promptset, resourceMgr, body, header)
 	case v20250326.PROTOCOL_VERSION:

internal/server/mcp/v20251125/method.go

@@ -0,0 +1,326 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v20251125
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/googleapis/genai-toolbox/internal/prompts"
+	"github.com/googleapis/genai-toolbox/internal/server/mcp/jsonrpc"
+	"github.com/googleapis/genai-toolbox/internal/server/resources"
+	"github.com/googleapis/genai-toolbox/internal/tools"
+	"github.com/googleapis/genai-toolbox/internal/util"
+)
+
+// ProcessMethod returns a response for the request.
+func ProcessMethod(ctx context.Context, id jsonrpc.RequestId, method string, toolset tools.Toolset, promptset prompts.Promptset, resourceMgr *resources.ResourceManager, body []byte, header http.Header) (any, error) {
+	switch method {
+	case PING:
+		return pingHandler(id)
+	case TOOLS_LIST:
+		return toolsListHandler(id, toolset, body)
+	case TOOLS_CALL:
+		return toolsCallHandler(ctx, id, resourceMgr, body, header)
+	case PROMPTS_LIST:
+		return promptsListHandler(ctx, id, promptset, body)
+	case PROMPTS_GET:
+		return promptsGetHandler(ctx, id, resourceMgr, body)
+	default:
+		err := fmt.Errorf("invalid method %s", method)
+		return jsonrpc.NewError(id, jsonrpc.METHOD_NOT_FOUND, err.Error(), nil), err
+	}
+}
+
+// pingHandler handles the "ping" method by returning an empty response.
+func pingHandler(id jsonrpc.RequestId) (any, error) {
+	return jsonrpc.JSONRPCResponse{
+		Jsonrpc: jsonrpc.JSONRPC_VERSION,
+		Id:      id,
+		Result:  struct{}{},
+	}, nil
+}
+
+func toolsListHandler(id jsonrpc.RequestId, toolset tools.Toolset, body []byte) (any, error) {
+	var req ListToolsRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		err = fmt.Errorf("invalid mcp tools list request: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+	}
+
+	result := ListToolsResult{
+		Tools: toolset.McpManifest,
+	}
+	return jsonrpc.JSONRPCResponse{
+		Jsonrpc: jsonrpc.JSONRPC_VERSION,
+		Id:      id,
+		Result:  result,
+	}, nil
+}
+
+// toolsCallHandler generate a response for tools call.
+func toolsCallHandler(ctx context.Context, id jsonrpc.RequestId, resourceMgr *resources.ResourceManager, body []byte, header http.Header) (any, error) {
+	authServices := resourceMgr.GetAuthServiceMap()
+
+	// retrieve logger from context
+	logger, err := util.LoggerFromContext(ctx)
+	if err != nil {
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+
+	var req CallToolRequest
+	if err = json.Unmarshal(body, &req); err != nil {
+		err = fmt.Errorf("invalid mcp tools call request: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+	}
+
+	toolName := req.Params.Name
+	toolArgument := req.Params.Arguments
+	logger.DebugContext(ctx, fmt.Sprintf("tool name: %s", toolName))
+	tool, ok := resourceMgr.GetTool(toolName)
+	if !ok {
+		err = fmt.Errorf("invalid tool name: tool with name %q does not exist", toolName)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_PARAMS, err.Error(), nil), err
+	}
+
+	// Get access token
+	authTokenHeadername, err := tool.GetAuthTokenHeaderName(resourceMgr)
+	if err != nil {
+		errMsg := fmt.Errorf("error during invocation: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, errMsg.Error(), nil), errMsg
+	}
+	accessToken := tools.AccessToken(header.Get(authTokenHeadername))
+
+	// Check if this specific tool requires the standard authorization header
+	clientAuth, err := tool.RequiresClientAuthorization(resourceMgr)
+	if err != nil {
+		errMsg := fmt.Errorf("error during invocation: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, errMsg.Error(), nil), errMsg
+	}
+	if clientAuth {
+		if accessToken == "" {
+			return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, "missing access token in the 'Authorization' header", nil), util.ErrUnauthorized
+		}
+	}
+
+	// marshal arguments and decode it using decodeJSON instead to prevent loss between floats/int.
+	aMarshal, err := json.Marshal(toolArgument)
+	if err != nil {
+		err = fmt.Errorf("unable to marshal tools argument: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+
+	var data map[string]any
+	if err = util.DecodeJSON(bytes.NewBuffer(aMarshal), &data); err != nil {
+		err = fmt.Errorf("unable to decode tools argument: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+
+	// Tool authentication
+	// claimsFromAuth maps the name of the authservice to the claims retrieved from it.
+	claimsFromAuth := make(map[string]map[string]any)
+
+	// if using stdio, header will be nil and auth will not be supported
+	if header != nil {
+		for _, aS := range authServices {
+			claims, err := aS.GetClaimsFromHeader(ctx, header)
+			if err != nil {
+				logger.DebugContext(ctx, err.Error())
+				continue
+			}
+			if claims == nil {
+				// authService not present in header
+				continue
+			}
+			claimsFromAuth[aS.GetName()] = claims
+		}
+	}
+
+	// Tool authorization check
+	verifiedAuthServices := make([]string, len(claimsFromAuth))
+	i := 0
+	for k := range claimsFromAuth {
+		verifiedAuthServices[i] = k
+		i++
+	}
+
+	// Check if any of the specified auth services is verified
+	isAuthorized := tool.Authorized(verifiedAuthServices)
+	if !isAuthorized {
+		err = fmt.Errorf("unauthorized Tool call: Please make sure your specify correct auth headers: %w", util.ErrUnauthorized)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, "tool invocation authorized")
+
+	params, err := tool.ParseParams(data, claimsFromAuth)
+	if err != nil {
+		err = fmt.Errorf("provided parameters were invalid: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_PARAMS, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, fmt.Sprintf("invocation params: %s", params))
+
+	// run tool invocation and generate response.
+	results, err := tool.Invoke(ctx, resourceMgr, params, accessToken)
+	if err != nil {
+		errStr := err.Error()
+		// Missing authService tokens.
+		if errors.Is(err, util.ErrUnauthorized) {
+			return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+		}
+		// Upstream auth error
+		if strings.Contains(errStr, "Error 401") || strings.Contains(errStr, "Error 403") {
+			if clientAuth {
+				// Error with client credentials should pass down to the client
+				return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+			}
+			// Auth error with ADC should raise internal 500 error
+			return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+		}
+		text := TextContent{
+			Type: "text",
+			Text: err.Error(),
+		}
+		return jsonrpc.JSONRPCResponse{
+			Jsonrpc: jsonrpc.JSONRPC_VERSION,
+			Id:      id,
+			Result:  CallToolResult{Content: []TextContent{text}, IsError: true},
+		}, nil
+	}
+
+	content := make([]TextContent, 0)
+
+	sliceRes, ok := results.([]any)
+	if !ok {
+		sliceRes = []any{results}
+	}
+
+	for _, d := range sliceRes {
+		text := TextContent{Type: "text"}
+		dM, err := json.Marshal(d)
+		if err != nil {
+			text.Text = fmt.Sprintf("fail to marshal: %s, result: %s", err, d)
+		} else {
+			text.Text = string(dM)
+		}
+		content = append(content, text)
+	}
+
+	return jsonrpc.JSONRPCResponse{
+		Jsonrpc: jsonrpc.JSONRPC_VERSION,
+		Id:      id,
+		Result:  CallToolResult{Content: content},
+	}, nil
+}
+
+// promptsListHandler handles the "prompts/list" method.
+func promptsListHandler(ctx context.Context, id jsonrpc.RequestId, promptset prompts.Promptset, body []byte) (any, error) {
+	// retrieve logger from context
+	logger, err := util.LoggerFromContext(ctx)
+	if err != nil {
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, "handling prompts/list request")
+
+	var req ListPromptsRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		err = fmt.Errorf("invalid mcp prompts list request: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+	}
+
+	result := ListPromptsResult{
+		Prompts: promptset.McpManifest,
+	}
+	logger.DebugContext(ctx, fmt.Sprintf("returning %d prompts", len(promptset.McpManifest)))
+	return jsonrpc.JSONRPCResponse{
+		Jsonrpc: jsonrpc.JSONRPC_VERSION,
+		Id:      id,
+		Result:  result,
+	}, nil
+}
+
+// promptsGetHandler handles the "prompts/get" method.
+func promptsGetHandler(ctx context.Context, id jsonrpc.RequestId, resourceMgr *resources.ResourceManager, body []byte) (any, error) {
+	// retrieve logger from context
+	logger, err := util.LoggerFromContext(ctx)
+	if err != nil {
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, "handling prompts/get request")
+
+	var req GetPromptRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		err = fmt.Errorf("invalid mcp prompts/get request: %w", err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_REQUEST, err.Error(), nil), err
+	}
+
+	promptName := req.Params.Name
+	logger.DebugContext(ctx, fmt.Sprintf("prompt name: %s", promptName))
+	prompt, ok := resourceMgr.GetPrompt(promptName)
+	if !ok {
+		err := fmt.Errorf("prompt with name %q does not exist", promptName)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_PARAMS, err.Error(), nil), err
+	}
+
+	// Parse the arguments provided in the request.
+	argValues, err := prompt.ParseArgs(req.Params.Arguments, nil)
+	if err != nil {
+		err = fmt.Errorf("invalid arguments for prompt %q: %w", promptName, err)
+		return jsonrpc.NewError(id, jsonrpc.INVALID_PARAMS, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, fmt.Sprintf("parsed args: %v", argValues))
+
+	// Substitute the argument values into the prompt's messages.
+	substituted, err := prompt.SubstituteParams(argValues)
+	if err != nil {
+		err = fmt.Errorf("error substituting params for prompt %q: %w", promptName, err)
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+
+	// Cast the result to the expected []prompts.Message type.
+	substitutedMessages, ok := substituted.([]prompts.Message)
+	if !ok {
+		err = fmt.Errorf("internal error: SubstituteParams returned unexpected type")
+		return jsonrpc.NewError(id, jsonrpc.INTERNAL_ERROR, err.Error(), nil), err
+	}
+	logger.DebugContext(ctx, "substituted params successfully")
+
+	// Format the response messages into the required structure.
+	promptMessages := make([]PromptMessage, len(substitutedMessages))
+	for i, msg := range substitutedMessages {
+		promptMessages[i] = PromptMessage{
+			Role: msg.Role,
+			Content: TextContent{
+				Type: "text",
+				Text: msg.Content,
+			},
+		}
+	}
+
+	result := GetPromptResult{
+		Description: prompt.Manifest().Description,
+		Messages:    promptMessages,
+	}
+
+	return jsonrpc.JSONRPCResponse{
+		Jsonrpc: jsonrpc.JSONRPC_VERSION,
+		Id:      id,
+		Result:  result,
+	}, nil
+}

internal/server/mcp/v20251125/types.go

@@ -0,0 +1,219 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v20251125
+
+import (
+	"github.com/googleapis/genai-toolbox/internal/prompts"
+	"github.com/googleapis/genai-toolbox/internal/server/mcp/jsonrpc"
+	"github.com/googleapis/genai-toolbox/internal/tools"
+)
+
+// SERVER_NAME is the server name used in Implementation.
+const SERVER_NAME = "Toolbox"
+
+// PROTOCOL_VERSION is the version of the MCP protocol in this package.
+const PROTOCOL_VERSION = "2025-11-25"
+
+// methods that are supported.
+const (
+	PING         = "ping"
+	TOOLS_LIST   = "tools/list"
+	TOOLS_CALL   = "tools/call"
+	PROMPTS_LIST = "prompts/list"
+	PROMPTS_GET  = "prompts/get"
+)
+
+/* Empty result */
+
+// EmptyResult represents a response that indicates success but carries no data.
+type EmptyResult jsonrpc.Result
+
+/* Pagination */
+
+// Cursor is an opaque token used to represent a cursor for pagination.
+type Cursor string
+
+type PaginatedRequest struct {
+	jsonrpc.Request
+	Params struct {
+		// An opaque token representing the current pagination position.
+		// If provided, the server should return results starting after this cursor.
+		Cursor Cursor `json:"cursor,omitempty"`
+	} `json:"params,omitempty"`
+}
+
+type PaginatedResult struct {
+	jsonrpc.Result
+	// An opaque token representing the pagination position after the last returned result.
+	// If present, there may be more results available.
+	NextCursor Cursor `json:"nextCursor,omitempty"`
+}
+
+/* Tools */
+
+// Sent from the client to request a list of tools the server has.
+type ListToolsRequest struct {
+	PaginatedRequest
+}
+
+// The server's response to a tools/list request from the client.
+type ListToolsResult struct {
+	PaginatedResult
+	Tools []tools.McpManifest `json:"tools"`
+}
+
+// Used by the client to invoke a tool provided by the server.
+type CallToolRequest struct {
+	jsonrpc.Request
+	Params struct {
+		Name      string         `json:"name"`
+		Arguments map[string]any `json:"arguments,omitempty"`
+	} `json:"params,omitempty"`
+}
+
+// The sender or recipient of messages and data in a conversation.
+type Role string
+
+const (
+	RoleUser      Role = "user"
+	RoleAssistant Role = "assistant"
+)
+
+// Base for objects that include optional annotations for the client.
+// The client can use annotations to inform how objects are used or displayed
+type Annotated struct {
+	Annotations *struct {
+		// Describes who the intended customer of this object or data is.
+		// It can include multiple entries to indicate content useful for multiple
+		// audiences (e.g., `["user", "assistant"]`).
+		Audience []Role `json:"audience,omitempty"`
+		// Describes how important this data is for operating the server.
+		//
+		// A value of 1 means "most important," and indicates that the data is
+		// effectively required, while 0 means "least important," and indicates that
+		// the data is entirely optional.
+		//
+		// @TJS-type number
+		// @minimum 0
+		// @maximum 1
+		Priority float64 `json:"priority,omitempty"`
+	} `json:"annotations,omitempty"`
+}
+
+// TextContent represents text provided to or from an LLM.
+type TextContent struct {
+	Annotated
+	Type string `json:"type"`
+	// The text content of the message.
+	Text string `json:"text"`
+}
+
+// The server's response to a tool call.
+//
+// Any errors that originate from the tool SHOULD be reported inside the result
+// object, with `isError` set to true, _not_ as an MCP protocol-level error
+// response. Otherwise, the LLM would not be able to see that an error occurred
+// and self-correct.
+//
+// However, any errors in _finding_ the tool, an error indicating that the
+// server does not support tool calls, or any other exceptional conditions,
+// should be reported as an MCP error response.
+type CallToolResult struct {
+	jsonrpc.Result
+	// Could be either a TextContent, ImageContent, or EmbeddedResources
+	// For Toolbox, we will only be sending TextContent
+	Content []TextContent `json:"content"`
+	// Whether the tool call ended in an error.
+	// If not set, this is assumed to be false (the call was successful).
+	//
+	// Any errors that originate from the tool SHOULD be reported inside the result
+	// object, with `isError` set to true, _not_ as an MCP protocol-level error
+	// response. Otherwise, the LLM would not be able to see that an error occurred
+	// and self-correct.
+	//
+	// However, any errors in _finding_ the tool, an error indicating that the
+	// server does not support tool calls, or any other exceptional conditions,
+	// should be reported as an MCP error response.
+	IsError bool `json:"isError,omitempty"`
+	// An optional JSON object that represents the structured result of the tool call.
+	StructuredContent map[string]any `json:"structuredContent,omitempty"`
+}
+
+// Additional properties describing a Tool to clients.
+//
+// NOTE: all properties in ToolAnnotations are **hints**.
+// They are not guaranteed to provide a faithful description of
+// tool behavior (including descriptive properties like `title`).
+//
+// Clients should never make tool use decisions based on ToolAnnotations
+// received from untrusted servers.
+type ToolAnnotations struct {
+	// A human-readable title for the tool.
+	Title string `json:"title,omitempty"`
+	// If true, the tool does not modify its environment.
+	// Default: false
+	ReadOnlyHint bool `json:"readOnlyHint,omitempty"`
+	// If true, the tool may perform destructive updates to its environment.
+	// If false, the tool performs only additive updates.
+	// (This property is meaningful only when `readOnlyHint == false`)
+	// Default: true
+	DestructiveHint bool `json:"destructiveHint,omitempty"`
+	// If true, calling the tool repeatedly with the same arguments
+	// will have no additional effect on the its environment.
+	// (This property is meaningful only when `readOnlyHint == false`)
+	// Default: false
+	IdempotentHint bool `json:"idempotentHint,omitempty"`
+	// If true, this tool may interact with an "open world" of external
+	// entities. If false, the tool's domain of interaction is closed.
+	// For example, the world of a web search tool is open, whereas that
+	// of a memory tool is not.
+	// Default: true
+	OpenWorldHint bool `json:"openWorldHint,omitempty"`
+}
+
+/* Prompts */
+
+// Sent from the client to request a list of prompts the server has.
+type ListPromptsRequest struct {
+	PaginatedRequest
+}
+
+// The server's response to a prompts/list request from the client.
+type ListPromptsResult struct {
+	PaginatedResult
+	Prompts []prompts.McpManifest `json:"prompts"`
+}
+
+// Used by the client to get a prompt provided by the server.
+type GetPromptRequest struct {
+	jsonrpc.Request
+	Params struct {
+		Name      string         `json:"name"`
+		Arguments map[string]any `json:"arguments,omitempty"`
+	} `json:"params"`
+}
+
+// The server's response to a prompts/get request from the client.
+type GetPromptResult struct {
+	jsonrpc.Result
+	Description string          `json:"description,omitempty"`
+	Messages    []PromptMessage `json:"messages"`
+}
+
+// Describes a message returned as part of a prompt.
+type PromptMessage struct {
+	Role    string      `json:"role"`
+	Content TextContent `json:"content"`
+}

internal/server/mcp_test.go

@@ -37,6 +37,7 @@ const jsonrpcVersion = "2.0"
 const protocolVersion20241105 = "2024-11-05"
 const protocolVersion20250326 = "2025-03-26"
 const protocolVersion20250618 = "2025-06-18"
+const protocolVersion20251125 = "2025-11-25"
 const serverName = "Toolbox"
 
 var basicInputSchema = map[string]any{
@@ -485,6 +486,23 @@ func TestMcpEndpoint(t *testing.T) {
 				},
 			},
 		},
+		{
+			name:     "version 2025-11-25",
+			protocol: protocolVersion20251125,
+			idHeader: false,
+			initWant: map[string]any{
+				"jsonrpc": "2.0",
+				"id":      "mcp-initialize",
+				"result": map[string]any{
+					"protocolVersion": "2025-11-25",
+					"capabilities": map[string]any{
+						"tools":   map[string]any{"listChanged": false},
+						"prompts": map[string]any{"listChanged": false},
+					},
+					"serverInfo": map[string]any{"name": serverName, "version": fakeVersionString},
+				},
+			},
+		},
 	}
 	for _, vtc := range versTestCases {
 		t.Run(vtc.name, func(t *testing.T) {
@@ -494,8 +512,7 @@ func TestMcpEndpoint(t *testing.T) {
 			if sessionId != "" {
 				header["Mcp-Session-Id"] = sessionId
 			}
-
-			if vtc.protocol == protocolVersion20250618 {
+			if vtc.protocol != protocolVersion20241105 && vtc.protocol != protocolVersion20250326 {
 				header["MCP-Protocol-Version"] = vtc.protocol
 			}
 

internal/server/resources/resources_test.go

@@ -32,7 +32,7 @@ func TestUpdateServer(t *testing.T) {
 		"example-source": &alloydbpg.Source{
 			Config: alloydbpg.Config{
 				Name: "example-alloydb-source",
-				Type: "alloydb-postgres",
+				Kind: "alloydb-postgres",
 			},
 		},
 	}
@@ -92,7 +92,7 @@ func TestUpdateServer(t *testing.T) {
 		"example-source2": &alloydbpg.Source{
 			Config: alloydbpg.Config{
 				Name: "example-alloydb-source2",
-				Type: "alloydb-postgres",
+				Kind: "alloydb-postgres",
 			},
 		},
 	}

internal/server/server.go

@@ -82,7 +82,7 @@ func InitializeConfigs(ctx context.Context, cfg ServerConfig) (
 			childCtx, span := instrumentation.Tracer.Start(
 				ctx,
 				"toolbox/server/source/init",
-				trace.WithAttributes(attribute.String("source_type", sc.SourceConfigType())),
+				trace.WithAttributes(attribute.String("source_kind", sc.SourceConfigKind())),
 				trace.WithAttributes(attribute.String("source_name", name)),
 			)
 			defer span.End()
@@ -110,7 +110,7 @@ func InitializeConfigs(ctx context.Context, cfg ServerConfig) (
 			_, span := instrumentation.Tracer.Start(
 				ctx,
 				"toolbox/server/auth/init",
-				trace.WithAttributes(attribute.String("auth_type", sc.AuthServiceConfigType())),
+				trace.WithAttributes(attribute.String("auth_kind", sc.AuthServiceConfigKind())),
 				trace.WithAttributes(attribute.String("auth_name", name)),
 			)
 			defer span.End()
@@ -138,7 +138,7 @@ func InitializeConfigs(ctx context.Context, cfg ServerConfig) (
 			_, span := instrumentation.Tracer.Start(
 				ctx,
 				"toolbox/server/embeddingmodel/init",
-				trace.WithAttributes(attribute.String("model_type", ec.EmbeddingModelConfigType())),
+				trace.WithAttributes(attribute.String("model_kind", ec.EmbeddingModelConfigKind())),
 				trace.WithAttributes(attribute.String("model_name", name)),
 			)
 			defer span.End()
@@ -166,7 +166,7 @@ func InitializeConfigs(ctx context.Context, cfg ServerConfig) (
 			_, span := instrumentation.Tracer.Start(
 				ctx,
 				"toolbox/server/tool/init",
-				trace.WithAttributes(attribute.String("tool_type", tc.ToolConfigType())),
+				trace.WithAttributes(attribute.String("tool_kind", tc.ToolConfigKind())),
 				trace.WithAttributes(attribute.String("tool_name", name)),
 			)
 			defer span.End()
@@ -235,7 +235,7 @@ func InitializeConfigs(ctx context.Context, cfg ServerConfig) (
 			_, span := instrumentation.Tracer.Start(
 				ctx,
 				"toolbox/server/prompt/init",
-				trace.WithAttributes(attribute.String("prompt_type", pc.PromptConfigType())),
+				trace.WithAttributes(attribute.String("prompt_kind", pc.PromptConfigKind())),
 				trace.WithAttributes(attribute.String("prompt_name", name)),
 			)
 			defer span.End()
@@ -304,10 +304,14 @@ func hostCheck(allowedHosts map[string]struct{}) func(http.Handler) http.Handler
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			_, hasWildcard := allowedHosts["*"]
-			_, hostIsAllowed := allowedHosts[r.Host]
+			hostname := r.Host
+			if host, _, err := net.SplitHostPort(r.Host); err == nil {
+				hostname = host
+			}
+			_, hostIsAllowed := allowedHosts[hostname]
 			if !hasWildcard && !hostIsAllowed {
-				// Return 400 Bad Request or 403 Forbidden to block the attack
-				http.Error(w, "Invalid Host header", http.StatusBadRequest)
+				// Return 403 Forbidden to block the attack
+				http.Error(w, "Invalid Host header", http.StatusForbidden)
 				return
 			}
 			next.ServeHTTP(w, r)
@@ -406,7 +410,11 @@ func NewServer(ctx context.Context, cfg ServerConfig) (*Server, error) {
 	}
 	allowedHostsMap := make(map[string]struct{}, len(cfg.AllowedHosts))
 	for _, h := range cfg.AllowedHosts {
-		allowedHostsMap[h] = struct{}{}
+		hostname := h
+		if host, _, err := net.SplitHostPort(h); err == nil {
+			hostname = host
+		}
+		allowedHostsMap[hostname] = struct{}{}
 	}
 	r.Use(hostCheck(allowedHostsMap))
 

internal/server/server_test.go

@@ -141,7 +141,7 @@ func TestUpdateServer(t *testing.T) {
 		"example-source": &alloydbpg.Source{
 			Config: alloydbpg.Config{
 				Name: "example-alloydb-source",
-				Type: "alloydb-postgres",
+				Kind: "alloydb-postgres",
 			},
 		},
 	}
@@ -200,3 +200,62 @@ func TestUpdateServer(t *testing.T) {
 		t.Errorf("error updating server, promptset (-want +got):\n%s", diff)
 	}
 }
+
+func TestNameValidation(t *testing.T) {
+	testCases := []struct {
+		desc         string
+		resourceName string
+		errStr       string
+	}{
+		{
+			desc:         "names with 0 length",
+			resourceName: "",
+			errStr:       "resource name SHOULD be between 1 and 128 characters in length (inclusive)",
+		},
+		{
+			desc:         "names with allowed length",
+			resourceName: "foo",
+		},
+		{
+			desc:         "names with 128 length",
+			resourceName: strings.Repeat("a", 128),
+		},
+		{
+			desc:         "names with more than 128 length",
+			resourceName: strings.Repeat("a", 129),
+			errStr:       "resource name SHOULD be between 1 and 128 characters in length (inclusive)",
+		},
+		{
+			desc:         "names with space",
+			resourceName: "foo bar",
+			errStr:       "invalid character for resource name; only uppercase and lowercase ASCII letters (A-Z, a-z), digits (0-9), underscore (_), hyphen (-), and dot (.) is allowed",
+		},
+		{
+			desc:         "names with commas",
+			resourceName: "foo,bar",
+			errStr:       "invalid character for resource name; only uppercase and lowercase ASCII letters (A-Z, a-z), digits (0-9), underscore (_), hyphen (-), and dot (.) is allowed",
+		},
+		{
+			desc:         "names with other special character",
+			resourceName: "foo!",
+			errStr:       "invalid character for resource name; only uppercase and lowercase ASCII letters (A-Z, a-z), digits (0-9), underscore (_), hyphen (-), and dot (.) is allowed",
+		},
+		{
+			desc:         "names with allowed special character",
+			resourceName: "foo_.-bar6",
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			err := server.NameValidation(tc.resourceName)
+			if err != nil {
+				if tc.errStr != err.Error() {
+					t.Fatalf("unexpected error: %s", err)
+				}
+			}
+			if err == nil && tc.errStr != "" {
+				t.Fatalf("expect error: %s", tc.errStr)
+			}
+		})
+	}
+}

internal/sources/alloydbadmin/alloydbadmin.go

@@ -32,14 +32,14 @@ import (
 	"google.golang.org/api/option"
 )
 
-const SourceType string = "alloydb-admin"
+const SourceKind string = "alloydb-admin"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -53,13 +53,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name           string `yaml:"name" validate:"required"`
-	Type           string `yaml:"type" validate:"required"`
+	Kind           string `yaml:"kind" validate:"required"`
 	DefaultProject string `yaml:"defaultProject"`
 	UseClientOAuth bool   `yaml:"useClientOAuth"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -106,8 +106,8 @@ type Source struct {
 	Service *alloydbrestapi.Service
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/alloydbadmin/alloydbadmin_test.go

@@ -15,9 +15,9 @@
 package alloydbadmin_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -34,14 +34,14 @@ func TestParseFromYamlAlloyDBAdmin(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-alloydb-admin-instance
-			type: alloydb-admin
+			sources:
+				my-alloydb-admin-instance:
+					kind: alloydb-admin
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-alloydb-admin-instance": alloydbadmin.Config{
 					Name:           "my-alloydb-admin-instance",
-					Type:           alloydbadmin.SourceType,
+					Kind:           alloydbadmin.SourceKind,
 					UseClientOAuth: false,
 				},
 			},
@@ -49,15 +49,15 @@ func TestParseFromYamlAlloyDBAdmin(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-alloydb-admin-instance
-			type: alloydb-admin
-			useClientOAuth: true
+			sources:
+				my-alloydb-admin-instance:
+					kind: alloydb-admin
+					useClientOAuth: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-alloydb-admin-instance": alloydbadmin.Config{
 					Name:           "my-alloydb-admin-instance",
-					Type:           alloydbadmin.SourceType,
+					Kind:           alloydbadmin.SourceKind,
 					UseClientOAuth: true,
 				},
 			},
@@ -65,13 +65,16 @@ func TestParseFromYamlAlloyDBAdmin(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
 			// Parse contents
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -86,27 +89,30 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-alloydb-admin-instance
-			type: alloydb-admin
-			project: test-project
+			sources:
+				my-alloydb-admin-instance:
+					kind: alloydb-admin
+					project: test-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-alloydb-admin-instance\" as \"alloydb-admin\": [2:1] unknown field \"project\"\n   1 | name: my-alloydb-admin-instance\n>  2 | project: test-project\n       ^\n   3 | type: alloydb-admin",
+			err: "unable to parse source \"my-alloydb-admin-instance\" as \"alloydb-admin\": [2:1] unknown field \"project\"\n   1 | kind: alloydb-admin\n>  2 | project: test-project\n       ^\n",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-alloydb-admin-instance
-			useClientOAuth: true
+			sources:
+				my-alloydb-admin-instance:
+					useClientOAuth: true
 			`,
-			err: "error unmarshaling sources: missing 'type' field or it is not a string",
+			err: "missing 'kind' field for source \"my-alloydb-admin-instance\"",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
 			// Parse contents
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/alloydbpg/alloydb_pg.go

@@ -29,14 +29,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "alloydb-postgres"
+const SourceKind string = "alloydb-postgres"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,7 +50,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string         `yaml:"name" validate:"required"`
-	Type     string         `yaml:"type" validate:"required"`
+	Kind     string         `yaml:"kind" validate:"required"`
 	Project  string         `yaml:"project" validate:"required"`
 	Region   string         `yaml:"region" validate:"required"`
 	Cluster  string         `yaml:"cluster" validate:"required"`
@@ -61,8 +61,8 @@ type Config struct {
 	Database string         `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -90,8 +90,8 @@ type Source struct {
 	Pool *pgxpool.Pool
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -183,7 +183,7 @@ func getConnectionConfig(ctx context.Context, user, pass, dbname string) (string
 
 func initAlloyDBPgConnectionPool(ctx context.Context, tracer trace.Tracer, name, project, region, cluster, instance, ipType, user, pass, dbname string) (*pgxpool.Pool, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	dsn, useIAM, err := getConnectionConfig(ctx, user, pass, dbname)

internal/sources/alloydbpg/alloydb_pg_test.go

@@ -15,9 +15,9 @@
 package alloydbpg_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -34,21 +34,21 @@ func TestParseFromYamlAlloyDBPg(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			project: my-project
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					project: my-project
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-pg-instance": alloydbpg.Config{
 					Name:     "my-pg-instance",
-					Type:     alloydbpg.SourceType,
+					Kind:     alloydbpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Cluster:  "my-cluster",
@@ -63,22 +63,22 @@ func TestParseFromYamlAlloyDBPg(t *testing.T) {
 		{
 			desc: "public ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			project: my-project
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			ipType: Public
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					project: my-project
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					ipType: Public
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-pg-instance": alloydbpg.Config{
 					Name:     "my-pg-instance",
-					Type:     alloydbpg.SourceType,
+					Kind:     alloydbpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Cluster:  "my-cluster",
@@ -93,22 +93,22 @@ func TestParseFromYamlAlloyDBPg(t *testing.T) {
 		{
 			desc: "private ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			project: my-project
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			ipType: private
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					project: my-project
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					ipType: private
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-pg-instance": alloydbpg.Config{
 					Name:     "my-pg-instance",
-					Type:     alloydbpg.SourceType,
+					Kind:     alloydbpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Cluster:  "my-cluster",
@@ -123,13 +123,16 @@ func TestParseFromYamlAlloyDBPg(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
 			// Parse contents
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -144,56 +147,60 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "invalid ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			project: my-project
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			ipType: fail 
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					project: my-project
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					ipType: fail 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
+			err: "unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
 		},
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			project: my-project
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					project: my-project
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": [3:1] unknown field \"foo\"\n   1 | cluster: my-cluster\n   2 | database: my_db\n>  3 | foo: bar\n       ^\n   4 | instance: my-instance\n   5 | name: my-pg-instance\n   6 | password: my_pass\n   7 | ",
+			err: "unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": [3:1] unknown field \"foo\"\n   1 | cluster: my-cluster\n   2 | database: my_db\n>  3 | foo: bar\n       ^\n   4 | instance: my-instance\n   5 | kind: alloydb-postgres\n   6 | password: my_pass\n   7 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: alloydb-postgres
-			region: my-region
-			cluster: my-cluster
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: alloydb-postgres
+					region: my-region
+					cluster: my-cluster
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-pg-instance\" as \"alloydb-postgres\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/bigquery/bigquery.go

@@ -41,7 +41,7 @@ import (
 	"google.golang.org/api/option"
 )
 
-const SourceType string = "bigquery"
+const SourceKind string = "bigquery"
 
 // CloudPlatformScope is a broad scope for Google Cloud Platform services.
 const CloudPlatformScope = "https://www.googleapis.com/auth/cloud-platform"
@@ -65,8 +65,8 @@ type BigQuerySessionProvider func(ctx context.Context) (*Session, error)
 type DataplexClientCreator func(tokenString string) (*dataplexapi.CatalogClient, error)
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -81,7 +81,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// BigQuery configs
 	Name                      string              `yaml:"name" validate:"required"`
-	Type                      string              `yaml:"type" validate:"required"`
+	Kind                      string              `yaml:"kind" validate:"required"`
 	Project                   string              `yaml:"project" validate:"required"`
 	Location                  string              `yaml:"location"`
 	WriteMode                 string              `yaml:"writeMode"`
@@ -119,9 +119,9 @@ func (s *StringOrStringSlice) UnmarshalYAML(unmarshal func(any) error) error {
 	return fmt.Errorf("cannot unmarshal %T into StringOrStringSlice", v)
 }
 
-func (r Config) SourceConfigType() string {
-	// Returns BigQuery source type
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	// Returns BigQuery source kind
+	return SourceKind
 }
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
 	if r.WriteMode == "" {
@@ -302,9 +302,9 @@ type Session struct {
 	LastUsed     time.Time
 }
 
-func (s *Source) SourceType() string {
-	// Returns BigQuery Google SQL source type
-	return SourceType
+func (s *Source) SourceKind() string {
+	// Returns BigQuery Google SQL source kind
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -665,7 +665,7 @@ func initBigQueryConnection(
 	impersonateServiceAccount string,
 	scopes []string,
 ) (*bigqueryapi.Client, *bigqueryrestapi.Service, oauth2.TokenSource, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)
@@ -741,7 +741,7 @@ func initBigQueryConnectionWithOAuthToken(
 	tokenString string,
 	wantRestService bool,
 ) (*bigqueryapi.Client, *bigqueryrestapi.Service, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 	// Construct token source
 	token := &oauth2.Token{
@@ -801,7 +801,7 @@ func initDataplexConnection(
 	var clientCreator DataplexClientCreator
 	var err error
 
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)

internal/sources/bigquery/bigquery_test.go

@@ -15,18 +15,18 @@
 package bigquery_test
 
 import (
-	"context"
 	"math/big"
 	"reflect"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
+	"go.opentelemetry.io/otel/trace/noop"
+
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/bigquery"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 	"github.com/googleapis/genai-toolbox/internal/util"
-	"go.opentelemetry.io/otel/trace/noop"
 )
 
 func TestParseFromYamlBigQuery(t *testing.T) {
@@ -38,15 +38,15 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:      "my-instance",
-					Type:      bigquery.SourceType,
+					Kind:      bigquery.SourceKind,
 					Project:   "my-project",
 					Location:  "",
 					WriteMode: "",
@@ -56,17 +56,17 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "all fields specified",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: asia
-			writeMode: blocked
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: asia
+					writeMode: blocked
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:           "my-instance",
-					Type:           bigquery.SourceType,
+					Kind:           bigquery.SourceKind,
 					Project:        "my-project",
 					Location:       "asia",
 					WriteMode:      "blocked",
@@ -77,17 +77,17 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			useClientOAuth: true
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					useClientOAuth: true
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:           "my-instance",
-					Type:           bigquery.SourceType,
+					Kind:           bigquery.SourceKind,
 					Project:        "my-project",
 					Location:       "us",
 					UseClientOAuth: true,
@@ -97,18 +97,18 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "with allowed datasets example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			allowedDatasets:
-			- my_dataset
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					allowedDatasets:
+						- my_dataset
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:            "my-instance",
-					Type:            bigquery.SourceType,
+					Kind:            bigquery.SourceKind,
 					Project:         "my-project",
 					Location:        "us",
 					AllowedDatasets: []string{"my_dataset"},
@@ -118,17 +118,17 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "with service account impersonation example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			impersonateServiceAccount: service-account@my-project.iam.gserviceaccount.com
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					impersonateServiceAccount: service-account@my-project.iam.gserviceaccount.com
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:                      "my-instance",
-					Type:                      bigquery.SourceType,
+					Kind:                      bigquery.SourceKind,
 					Project:                   "my-project",
 					Location:                  "us",
 					ImpersonateServiceAccount: "service-account@my-project.iam.gserviceaccount.com",
@@ -138,19 +138,19 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "with custom scopes example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			scopes:
-			- https://www.googleapis.com/auth/bigquery
-			- https://www.googleapis.com/auth/cloud-platform
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					scopes:
+						- https://www.googleapis.com/auth/bigquery
+						- https://www.googleapis.com/auth/cloud-platform
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:     "my-instance",
-					Type:     bigquery.SourceType,
+					Kind:     bigquery.SourceKind,
 					Project:  "my-project",
 					Location: "us",
 					Scopes:   []string{"https://www.googleapis.com/auth/bigquery", "https://www.googleapis.com/auth/cloud-platform"},
@@ -160,17 +160,17 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 		{
 			desc: "with max query result rows example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			maxQueryResultRows: 10
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					maxQueryResultRows: 10
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": bigquery.Config{
 					Name:               "my-instance",
-					Type:               bigquery.SourceType,
+					Kind:               bigquery.SourceKind,
 					Project:            "my-project",
 					Location:           "us",
 					MaxQueryResultRows: 10,
@@ -180,15 +180,20 @@ func TestParseFromYamlBigQuery(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if diff := cmp.Diff(tc.want, got); diff != "" {
-				t.Fatalf("incorrect parse (-want +got):\n%s", diff)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
+
 }
 
 func TestFailParseFromYaml(t *testing.T) {
@@ -200,29 +205,33 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			project: my-project
-			location: us
-			foo: bar
+			sources:
+				my-instance:
+					kind: bigquery
+					project: my-project
+					location: us
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"bigquery\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | location: us\n   3 | name: my-instance\n   4 | project: my-project\n   5 | ",
+			err: "unable to parse source \"my-instance\" as \"bigquery\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | kind: bigquery\n   3 | location: us\n   4 | project: my-project",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: bigquery
-			location: us
+			sources:
+				my-instance:
+					kind: bigquery
+					location: us
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"bigquery\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-instance\" as \"bigquery\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}
@@ -251,7 +260,7 @@ func TestInitialize_MaxQueryResultRows(t *testing.T) {
 			desc: "default value",
 			cfg: bigquery.Config{
 				Name:           "test-default",
-				Type:           bigquery.SourceType,
+				Kind:           bigquery.SourceKind,
 				Project:        "test-project",
 				UseClientOAuth: true,
 			},
@@ -261,7 +270,7 @@ func TestInitialize_MaxQueryResultRows(t *testing.T) {
 			desc: "configured value",
 			cfg: bigquery.Config{
 				Name:               "test-configured",
-				Type:               bigquery.SourceType,
+				Kind:               bigquery.SourceKind,
 				Project:            "test-project",
 				UseClientOAuth:     true,
 				MaxQueryResultRows: 100,

internal/sources/bigtable/bigtable.go

@@ -27,14 +27,14 @@ import (
 	"google.golang.org/api/option"
 )
 
-const SourceType string = "bigtable"
+const SourceKind string = "bigtable"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -48,13 +48,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Project  string `yaml:"project" validate:"required"`
 	Instance string `yaml:"instance" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -77,8 +77,8 @@ type Source struct {
 	Client *bigtable.Client
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -179,7 +179,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, configParam param
 
 func initBigtableClient(ctx context.Context, tracer trace.Tracer, name, project, instance string) (*bigtable.Client, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Set up Bigtable data operations client.

internal/sources/bigtable/bigtable_test.go

@@ -15,9 +15,9 @@
 package bigtable_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -34,16 +34,16 @@ func TestParseFromYamlBigtableDb(t *testing.T) {
 		{
 			desc: "can configure with a bigtable table",
 			in: `
-			kind: sources
-			name: my-bigtable-instance
-			type: bigtable
-			project: my-project
-			instance: my-instance
+			sources:
+				my-bigtable-instance:
+					kind: bigtable
+					project: my-project
+					instance: my-instance
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-bigtable-instance": bigtable.Config{
 					Name:     "my-bigtable-instance",
-					Type:     bigtable.SourceType,
+					Kind:     bigtable.SourceKind,
 					Project:  "my-project",
 					Instance: "my-instance",
 				},
@@ -52,12 +52,16 @@ func TestParseFromYamlBigtableDb(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -73,29 +77,33 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-bigtable-instance
-			type: bigtable
-			project: my-project
-			instance: my-instance
-			foo: bar
+			sources:
+				my-bigtable-instance:
+					kind: bigtable
+					project: my-project
+					instance: my-instance
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-bigtable-instance\" as \"bigtable\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | instance: my-instance\n   3 | name: my-bigtable-instance\n   4 | project: my-project\n   5 | ",
+			err: "unable to parse source \"my-bigtable-instance\" as \"bigtable\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | instance: my-instance\n   3 | kind: bigtable\n   4 | project: my-project",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-bigtable-instance
-			type: bigtable
-			project: my-project
+			sources:
+				my-bigtable-instance:
+					kind: bigtable
+					project: my-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-bigtable-instance\" as \"bigtable\": Key: 'Config.Instance' Error:Field validation for 'Instance' failed on the 'required' tag",
+			err: "unable to parse source \"my-bigtable-instance\" as \"bigtable\": Key: 'Config.Instance' Error:Field validation for 'Instance' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cassandra/cassandra.go

@@ -25,11 +25,11 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "cassandra"
+const SourceKind string = "cassandra"
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -43,7 +43,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name                   string   `yaml:"name" validate:"required"`
-	Type                   string   `yaml:"type" validate:"required"`
+	Kind                   string   `yaml:"kind" validate:"required"`
 	Hosts                  []string `yaml:"hosts" validate:"required"`
 	Keyspace               string   `yaml:"keyspace"`
 	ProtoVersion           int      `yaml:"protoVersion"`
@@ -68,9 +68,9 @@ func (c Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.So
 	return s, nil
 }
 
-// SourceConfigType implements sources.SourceConfig.
-func (c Config) SourceConfigType() string {
-	return SourceType
+// SourceConfigKind implements sources.SourceConfig.
+func (c Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 var _ sources.SourceConfig = Config{}
@@ -89,9 +89,9 @@ func (s *Source) ToConfig() sources.SourceConfig {
 	return s.Config
 }
 
-// SourceType implements sources.Source.
-func (s *Source) SourceType() string {
-	return SourceType
+// SourceKind implements sources.Source.
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) RunSQL(ctx context.Context, statement string, params parameters.ParamValues) (any, error) {
@@ -120,7 +120,7 @@ var _ sources.Source = &Source{}
 
 func initCassandraSession(ctx context.Context, tracer trace.Tracer, c Config) (*gocql.Session, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, c.Name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, c.Name)
 	defer span.End()
 
 	// Validate authentication configuration

internal/sources/cassandra/cassandra_test.go

@@ -15,12 +15,11 @@
 package cassandra_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/cassandra"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,17 +33,17 @@ func TestParseFromYamlCassandra(t *testing.T) {
 		{
 			desc: "basic example (without optional fields)",
 			in: `
-			kind: sources
-			name: my-cassandra-instance
-			type: cassandra
-			hosts:
-				- "my-host1"
-				- "my-host2"
+			sources:
+				my-cassandra-instance:
+					kind: cassandra
+					hosts:
+						- "my-host1"
+						- "my-host2"
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-cassandra-instance": cassandra.Config{
 					Name:                   "my-cassandra-instance",
-					Type:                   cassandra.SourceType,
+					Kind:                   cassandra.SourceKind,
 					Hosts:                  []string{"my-host1", "my-host2"},
 					Username:               "",
 					Password:               "",
@@ -60,25 +59,25 @@ func TestParseFromYamlCassandra(t *testing.T) {
 		{
 			desc: "with optional fields",
 			in: `
-			kind: sources
-			name: my-cassandra-instance
-			type: cassandra
-			hosts:
-				- "my-host1"
-				- "my-host2"
-			username: "user"
-			password: "pass"
-			keyspace: "example_keyspace"
-			protoVersion: 4
-			caPath: "path/to/ca.crt"
-			certPath: "path/to/cert"
-			keyPath: "path/to/key"
-			enableHostVerification: true
+			sources:
+				my-cassandra-instance:
+					kind: cassandra
+					hosts:
+						- "my-host1"
+						- "my-host2"
+					username: "user"
+					password: "pass"
+					keyspace: "example_keyspace"
+					protoVersion: 4
+					caPath: "path/to/ca.crt"
+					certPath: "path/to/cert"
+					keyPath: "path/to/key"
+					enableHostVerification: true
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-cassandra-instance": cassandra.Config{
 					Name:                   "my-cassandra-instance",
-					Type:                   cassandra.SourceType,
+					Kind:                   cassandra.SourceKind,
 					Hosts:                  []string{"my-host1", "my-host2"},
 					Username:               "user",
 					Password:               "pass",
@@ -94,12 +93,16 @@ func TestParseFromYamlCassandra(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -115,29 +118,33 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-cassandra-instance
-			type: cassandra
-			hosts:
-				- "my-host"
-			foo: bar
+			sources:
+				my-cassandra-instance:
+					kind: cassandra
+					hosts:
+						- "my-host"
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-cassandra-instance\" as \"cassandra\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | hosts:\n   3 | - my-host\n   4 | name: my-cassandra-instance\n   5 | ",
+			err: "unable to parse source \"my-cassandra-instance\" as \"cassandra\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | hosts:\n   3 | - my-host\n   4 | kind: cassandra",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-cassandra-instance
-			type: cassandra
+			sources:
+				my-cassandra-instance:
+					kind: cassandra
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-cassandra-instance\" as \"cassandra\": Key: 'Config.Hosts' Error:Field validation for 'Hosts' failed on the 'required' tag",
+			err: "unable to parse source \"my-cassandra-instance\" as \"cassandra\": Key: 'Config.Hosts' Error:Field validation for 'Hosts' failed on the 'required' tag",
 		},
 	}
 
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/clickhouse/clickhouse.go

@@ -28,14 +28,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "clickhouse"
+const SourceKind string = "clickhouse"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -49,7 +49,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Host     string `yaml:"host" validate:"required"`
 	Port     string `yaml:"port" validate:"required"`
 	Database string `yaml:"database" validate:"required"`
@@ -59,8 +59,8 @@ type Config struct {
 	Secure   bool   `yaml:"secure"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -88,8 +88,8 @@ type Source struct {
 	Pool *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -174,7 +174,7 @@ func validateConfig(protocol string) error {
 
 func initClickHouseConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname, protocol string, secure bool) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	if protocol == "" {

internal/sources/clickhouse/clickhouse_test.go

@@ -21,113 +21,137 @@ import (
 
 	"github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
-	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 	"go.opentelemetry.io/otel"
 )
 
-func TestParseFromYamlClickhouse(t *testing.T) {
-	tcs := []struct {
-		desc string
-		in   string
-		want server.SourceConfigs
-	}{
-		{
-			desc: "all fields specified",
-			in: `
-			kind: sources
-			name: test-clickhouse
-			type: clickhouse
-			host: localhost
-			port: "8443"
-			user: default
-			password: "mypass"
-			database: mydb
-			protocol: https
-			secure: true
-			`,
-			want: map[string]sources.SourceConfig{
-				"test-clickhouse": Config{
-					Name:     "test-clickhouse",
-					Type:     "clickhouse",
-					Host:     "localhost",
-					Port:     "8443",
-					User:     "default",
-					Password: "mypass",
-					Database: "mydb",
-					Protocol: "https",
-					Secure:   true,
-				},
-			},
-		},
-		{
-			desc: "minimal configuration with defaults",
-			in: `
-			kind: sources
-			name: minimal-clickhouse
-			type: clickhouse
-			host: 127.0.0.1
-			port: "8123"
-			user: testuser
-			database: testdb
-			`,
-			want: map[string]sources.SourceConfig{
-				"minimal-clickhouse": Config{
-					Name:     "minimal-clickhouse",
-					Type:     "clickhouse",
-					Host:     "127.0.0.1",
-					Port:     "8123",
-					User:     "testuser",
-					Password: "",
-					Database: "testdb",
-					Protocol: "",
-					Secure:   false,
-				},
-			},
-		},
-	}
-	for _, tc := range tcs {
-		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
-			if err != nil {
-				t.Fatalf("unable to unmarshal: %s", err)
-			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
-			}
-		})
+func TestConfigSourceConfigKind(t *testing.T) {
+	config := Config{}
+	if config.SourceConfigKind() != SourceKind {
+		t.Errorf("Expected %s, got %s", SourceKind, config.SourceConfigKind())
 	}
 }
 
-func TestFailParseFromYaml(t *testing.T) {
-	tcs := []struct {
-		desc string
-		in   string
-		err  string
+func TestNewConfig(t *testing.T) {
+	tests := []struct {
+		name     string
+		yaml     string
+		expected Config
 	}{
 		{
-			desc: "extra field",
-			in: `
-			kind: sources
-			name: test-clickhouse
-			type: clickhouse
-			host: localhost
-			foo: bar
+			name: "all fields specified",
+			yaml: `
+				name: test-clickhouse
+				kind: clickhouse
+				host: localhost
+				port: "8443"
+				user: default
+				password: "mypass"
+				database: mydb
+				protocol: https
+				secure: true
 			`,
-			err: "error unmarshaling sources: unable to parse source \"test-clickhouse\" as \"clickhouse\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | host: localhost\n   3 | name: test-clickhouse\n   4 | type: clickhouse",
+			expected: Config{
+				Name:     "test-clickhouse",
+				Kind:     "clickhouse",
+				Host:     "localhost",
+				Port:     "8443",
+				User:     "default",
+				Password: "mypass",
+				Database: "mydb",
+				Protocol: "https",
+				Secure:   true,
+			},
+		},
+		{
+			name: "minimal configuration with defaults",
+			yaml: `
+				name: minimal-clickhouse
+				kind: clickhouse
+				host: 127.0.0.1
+				port: "8123"
+				user: testuser
+				database: testdb
+			`,
+			expected: Config{
+				Name:     "minimal-clickhouse",
+				Kind:     "clickhouse",
+				Host:     "127.0.0.1",
+				Port:     "8123",
+				User:     "testuser",
+				Password: "",
+				Database: "testdb",
+				Protocol: "",
+				Secure:   false,
+			},
+		},
+		{
+			name: "http protocol",
+			yaml: `
+				name: http-clickhouse
+				kind: clickhouse
+				host: clickhouse.example.com
+				port: "8123"
+				user: analytics
+				password: "securepass"
+				database: analytics_db
+				protocol: http
+				secure: false
+			`,
+			expected: Config{
+				Name:     "http-clickhouse",
+				Kind:     "clickhouse",
+				Host:     "clickhouse.example.com",
+				Port:     "8123",
+				User:     "analytics",
+				Password: "securepass",
+				Database: "analytics_db",
+				Protocol: "http",
+				Secure:   false,
+			},
+		},
+		{
+			name: "https with secure connection",
+			yaml: `
+				name: secure-clickhouse
+				kind: clickhouse
+				host: secure.clickhouse.io
+				port: "8443"
+				user: secureuser
+				password: "verysecure"
+				database: production
+				protocol: https
+				secure: true
+			`,
+			expected: Config{
+				Name:     "secure-clickhouse",
+				Kind:     "clickhouse",
+				Host:     "secure.clickhouse.io",
+				Port:     "8443",
+				User:     "secureuser",
+				Password: "verysecure",
+				Database: "production",
+				Protocol: "https",
+				Secure:   true,
+			},
 		},
 	}
 
-	for _, tc := range tcs {
-		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
-			if err == nil {
-				t.Fatalf("expect parsing to fail")
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			decoder := yaml.NewDecoder(strings.NewReader(string(testutils.FormatYaml(tt.yaml))))
+			config, err := newConfig(context.Background(), tt.expected.Name, decoder)
+			if err != nil {
+				t.Fatalf("Failed to create config: %v", err)
 			}
-			errStr := err.Error()
-			if errStr != tc.err {
-				t.Fatalf("unexpected error: got %q, want %q", errStr, tc.err)
+
+			clickhouseConfig, ok := config.(Config)
+			if !ok {
+				t.Fatalf("Expected Config type, got %T", config)
+			}
+
+			if diff := cmp.Diff(tt.expected, clickhouseConfig); diff != "" {
+				t.Errorf("Config mismatch (-want +got):\n%s", diff)
 			}
 		})
 	}
@@ -143,11 +167,19 @@ func TestNewConfigInvalidYAML(t *testing.T) {
 			name: "invalid yaml syntax",
 			yaml: `
 				name: test-clickhouse
-				type: clickhouse
+				kind: clickhouse
 				host: [invalid
 			`,
 			expectError: true,
 		},
+		{
+			name: "missing required fields",
+			yaml: `
+				name: test-clickhouse
+				kind: clickhouse
+			`,
+			expectError: false,
+		},
 	}
 
 	for _, tt := range tests {
@@ -164,10 +196,10 @@ func TestNewConfigInvalidYAML(t *testing.T) {
 	}
 }
 
-func TestSource_SourceType(t *testing.T) {
+func TestSource_SourceKind(t *testing.T) {
 	source := &Source{}
-	if source.SourceType() != SourceType {
-		t.Errorf("Expected %s, got %s", SourceType, source.SourceType())
+	if source.SourceKind() != SourceKind {
+		t.Errorf("Expected %s, got %s", SourceKind, source.SourceKind())
 	}
 }
 

internal/sources/cloudgda/cloud_gda.go

@@ -29,15 +29,15 @@ import (
 	"golang.org/x/oauth2/google"
 )
 
-const SourceType string = "cloud-gemini-data-analytics"
+const SourceKind string = "cloud-gemini-data-analytics"
 const Endpoint string = "https://geminidataanalytics.googleapis.com"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,13 +51,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name           string `yaml:"name" validate:"required"`
-	Type           string `yaml:"type" validate:"required"`
+	Kind           string `yaml:"kind" validate:"required"`
 	ProjectID      string `yaml:"projectId" validate:"required"`
 	UseClientOAuth bool   `yaml:"useClientOAuth"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize initializes a Gemini Data Analytics Source instance.
@@ -102,8 +102,8 @@ type Source struct {
 	userAgent string
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/cloudgda/cloud_gda_test.go

@@ -20,6 +20,7 @@ import (
 	"path/filepath"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -38,15 +39,15 @@ func TestParseFromYamlCloudGDA(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-gda-instance
-			type: cloud-gemini-data-analytics
-			projectId: test-project-id
-			`,
+		            sources:
+		                my-gda-instance:
+		                    kind: cloud-gemini-data-analytics
+		                    projectId: test-project-id
+		            `,
 			want: map[string]sources.SourceConfig{
 				"my-gda-instance": cloudgda.Config{
 					Name:           "my-gda-instance",
-					Type:           cloudgda.SourceType,
+					Kind:           cloudgda.SourceKind,
 					ProjectID:      "test-project-id",
 					UseClientOAuth: false,
 				},
@@ -55,16 +56,16 @@ func TestParseFromYamlCloudGDA(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-gda-instance
-			type: cloud-gemini-data-analytics
-			projectId: another-project
-			useClientOAuth: true
+			sources:
+				my-gda-instance:
+					kind: cloud-gemini-data-analytics
+					projectId: another-project
+					useClientOAuth: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-gda-instance": cloudgda.Config{
 					Name:           "my-gda-instance",
-					Type:           cloudgda.SourceType,
+					Kind:           cloudgda.SourceKind,
 					ProjectID:      "another-project",
 					UseClientOAuth: true,
 				},
@@ -75,12 +76,16 @@ func TestParseFromYamlCloudGDA(t *testing.T) {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -96,18 +101,22 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "missing projectId",
 			in: `
-			kind: sources
-			name: my-gda-instance
-			type: cloud-gemini-data-analytics
+			sources:
+				my-gda-instance:
+					kind: cloud-gemini-data-analytics
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-gda-instance\" as \"cloud-gemini-data-analytics\": Key: 'Config.ProjectID' Error:Field validation for 'ProjectID' failed on the 'required' tag",
+			err: "unable to parse source \"my-gda-instance\" as \"cloud-gemini-data-analytics\": Key: 'Config.ProjectID' Error:Field validation for 'ProjectID' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}
@@ -144,12 +153,12 @@ func TestInitialize(t *testing.T) {
 	}{
 		{
 			desc:            "initialize with ADC",
-			cfg:             cloudgda.Config{Name: "test-gda", Type: cloudgda.SourceType, ProjectID: "test-proj"},
+			cfg:             cloudgda.Config{Name: "test-gda", Kind: cloudgda.SourceKind, ProjectID: "test-proj"},
 			wantClientOAuth: false,
 		},
 		{
 			desc:            "initialize with client OAuth",
-			cfg:             cloudgda.Config{Name: "test-gda-oauth", Type: cloudgda.SourceType, ProjectID: "test-proj", UseClientOAuth: true},
+			cfg:             cloudgda.Config{Name: "test-gda-oauth", Kind: cloudgda.SourceKind, ProjectID: "test-proj", UseClientOAuth: true},
 			wantClientOAuth: true,
 		},
 	}

internal/sources/cloudhealthcare/cloud_healthcare.go

@@ -34,7 +34,7 @@ import (
 	"google.golang.org/api/option"
 )
 
-const SourceType string = "cloud-healthcare"
+const SourceKind string = "cloud-healthcare"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
@@ -42,8 +42,8 @@ var _ sources.SourceConfig = Config{}
 type HealthcareServiceCreator func(tokenString string) (*healthcare.Service, error)
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -58,7 +58,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// Healthcare configs
 	Name               string   `yaml:"name" validate:"required"`
-	Type               string   `yaml:"type" validate:"required"`
+	Kind               string   `yaml:"kind" validate:"required"`
 	Project            string   `yaml:"project" validate:"required"`
 	Region             string   `yaml:"region" validate:"required"`
 	Dataset            string   `yaml:"dataset" validate:"required"`
@@ -67,8 +67,8 @@ type Config struct {
 	UseClientOAuth     bool     `yaml:"useClientOAuth"`
 }
 
-func (c Config) SourceConfigType() string {
-	return SourceType
+func (c Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (c Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -144,7 +144,7 @@ func newHealthcareServiceCreator(ctx context.Context, tracer trace.Tracer, name
 }
 
 func initHealthcareConnectionWithOAuthToken(ctx context.Context, tracer trace.Tracer, name string, userAgent string, tokenString string) (*healthcare.Service, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 	// Construct token source
 	token := &oauth2.Token{
@@ -162,7 +162,7 @@ func initHealthcareConnectionWithOAuthToken(ctx context.Context, tracer trace.Tr
 }
 
 func initHealthcareConnection(ctx context.Context, tracer trace.Tracer, name string) (*healthcare.Service, oauth2.TokenSource, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	cred, err := google.FindDefaultCredentials(ctx, healthcare.CloudHealthcareScope)
@@ -194,8 +194,8 @@ type Source struct {
 	allowedDICOMStores map[string]struct{}
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -517,14 +517,14 @@ func (s *Source) RetrieveRenderedDICOMInstance(storeID, study, series, sop strin
 	return base64String, nil
 }
 
-func (s *Source) SearchDICOM(toolType, storeID, dicomWebPath, tokenStr string, opts []googleapi.CallOption) (any, error) {
+func (s *Source) SearchDICOM(toolKind, storeID, dicomWebPath, tokenStr string, opts []googleapi.CallOption) (any, error) {
 	svc, err := s.getService(tokenStr)
 	if err != nil {
 		return nil, err
 	}
 	name := fmt.Sprintf("projects/%s/locations/%s/datasets/%s/dicomStores/%s", s.Project(), s.Region(), s.DatasetID(), storeID)
 	var resp *http.Response
-	switch toolType {
+	switch toolKind {
 	case "cloud-healthcare-search-dicom-instances":
 		resp, err = svc.Projects.Locations.Datasets.DicomStores.SearchForInstances(name, dicomWebPath).Do(opts...)
 	case "cloud-healthcare-search-dicom-series":
@@ -532,7 +532,7 @@ func (s *Source) SearchDICOM(toolType, storeID, dicomWebPath, tokenStr string, o
 	case "cloud-healthcare-search-dicom-studies":
 		resp, err = svc.Projects.Locations.Datasets.DicomStores.SearchForStudies(name, dicomWebPath).Do(opts...)
 	default:
-		return nil, fmt.Errorf("incompatible tool type: %s", toolType)
+		return nil, fmt.Errorf("incompatible tool kind: %s", toolKind)
 	}
 	if err != nil {
 		return nil, fmt.Errorf("failed to search dicom series: %w", err)

internal/sources/cloudhealthcare/cloud_healthcare_test.go

@@ -15,12 +15,11 @@
 package cloudhealthcare_test
 
 import (
-	"context"
 	"testing"
 
+	"github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/cloudhealthcare"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,17 +33,17 @@ func TestParseFromYamlCloudHealthcare(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-healthcare
-			project: my-project
-			region: us-central1
-			dataset: my-dataset
+				sources:
+					my-instance:
+						kind: cloud-healthcare
+						project: my-project
+						region: us-central1
+						dataset: my-dataset
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudhealthcare.Config{
 					Name:           "my-instance",
-					Type:           cloudhealthcare.SourceType,
+					Kind:           cloudhealthcare.SourceKind,
 					Project:        "my-project",
 					Region:         "us-central1",
 					Dataset:        "my-dataset",
@@ -55,18 +54,18 @@ func TestParseFromYamlCloudHealthcare(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-healthcare
-			project: my-project
-			region: us
-			dataset: my-dataset
-			useClientOAuth: true
+			sources:
+				my-instance:
+					kind: cloud-healthcare
+					project: my-project
+					region: us
+					dataset: my-dataset
+					useClientOAuth: true
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudhealthcare.Config{
 					Name:           "my-instance",
-					Type:           cloudhealthcare.SourceType,
+					Kind:           cloudhealthcare.SourceKind,
 					Project:        "my-project",
 					Region:         "us",
 					Dataset:        "my-dataset",
@@ -77,22 +76,22 @@ func TestParseFromYamlCloudHealthcare(t *testing.T) {
 		{
 			desc: "with allowed stores example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-healthcare
-			project: my-project
-			region: us
-			dataset: my-dataset
-			allowedFhirStores:
-				- my-fhir-store
-			allowedDicomStores:
-				- my-dicom-store1
-				- my-dicom-store2
+			sources:
+				my-instance:
+					kind: cloud-healthcare
+					project: my-project
+					region: us
+					dataset: my-dataset
+					allowedFhirStores:
+						- my-fhir-store
+					allowedDicomStores:
+						- my-dicom-store1
+						- my-dicom-store2
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudhealthcare.Config{
 					Name:               "my-instance",
-					Type:               cloudhealthcare.SourceType,
+					Kind:               cloudhealthcare.SourceKind,
 					Project:            "my-project",
 					Region:             "us",
 					Dataset:            "my-dataset",
@@ -104,12 +103,16 @@ func TestParseFromYamlCloudHealthcare(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -124,31 +127,35 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-healthcare
-			project: my-project
-			region: us-central1
-			dataset: my-dataset
-			foo: bar
+			sources:
+				my-instance:
+					kind: cloud-healthcare
+					project: my-project
+					region: us-central1
+					dataset: my-dataset
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"cloud-healthcare\": [2:1] unknown field \"foo\"\n   1 | dataset: my-dataset\n>  2 | foo: bar\n       ^\n   3 | name: my-instance\n   4 | project: my-project\n   5 | region: us-central1\n   6 | ",
+			err: "unable to parse source \"my-instance\" as \"cloud-healthcare\": [2:1] unknown field \"foo\"\n   1 | dataset: my-dataset\n>  2 | foo: bar\n       ^\n   3 | kind: cloud-healthcare\n   4 | project: my-project\n   5 | region: us-central1",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-healthcare
-			project: my-project
-			region: us-central1
+			sources:
+				my-instance:
+					kind: cloud-healthcare
+					project: my-project
+					region: us-central1
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"cloud-healthcare\": Key: 'Config.Dataset' Error:Field validation for 'Dataset' failed on the 'required' tag",
+			err: `unable to parse source "my-instance" as "cloud-healthcare": Key: 'Config.Dataset' Error:Field validation for 'Dataset' failed on the 'required' tag`,
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cloudmonitoring/cloud_monitoring.go

@@ -29,14 +29,14 @@ import (
 	monitoring "google.golang.org/api/monitoring/v3"
 )
 
-const SourceType string = "cloud-monitoring"
+const SourceKind string = "cloud-monitoring"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,12 +50,12 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name           string `yaml:"name" validate:"required"`
-	Type           string `yaml:"type" validate:"required"`
+	Kind           string `yaml:"kind" validate:"required"`
 	UseClientOAuth bool   `yaml:"useClientOAuth"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize initializes a Cloud Monitoring Source instance.
@@ -99,8 +99,8 @@ type Source struct {
 	userAgent string
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/cloudmonitoring/cloud_monitoring_test.go

@@ -15,9 +15,9 @@
 package cloudmonitoring_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -35,14 +35,14 @@ func TestParseFromYamlCloudMonitoring(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-cloud-monitoring-instance
-			type: cloud-monitoring
+			sources:
+				my-cloud-monitoring-instance:
+					kind: cloud-monitoring
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-cloud-monitoring-instance": cloudmonitoring.Config{
 					Name:           "my-cloud-monitoring-instance",
-					Type:           cloudmonitoring.SourceType,
+					Kind:           cloudmonitoring.SourceKind,
 					UseClientOAuth: false,
 				},
 			},
@@ -50,15 +50,15 @@ func TestParseFromYamlCloudMonitoring(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-cloud-monitoring-instance
-			type: cloud-monitoring
-			useClientOAuth: true
+			sources:
+				my-cloud-monitoring-instance:
+					kind: cloud-monitoring
+					useClientOAuth: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-cloud-monitoring-instance": cloudmonitoring.Config{
 					Name:           "my-cloud-monitoring-instance",
-					Type:           cloudmonitoring.SourceType,
+					Kind:           cloudmonitoring.SourceKind,
 					UseClientOAuth: true,
 				},
 			},
@@ -68,12 +68,16 @@ func TestParseFromYamlCloudMonitoring(t *testing.T) {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -89,28 +93,36 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-cloud-monitoring-instance
-			type: cloud-monitoring
-			project: test-project
+			sources:
+				my-cloud-monitoring-instance:
+					kind: cloud-monitoring
+					project: test-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-cloud-monitoring-instance\" as \"cloud-monitoring\": [2:1] unknown field \"project\"\n   1 | name: my-cloud-monitoring-instance\n>  2 | project: test-project\n       ^\n   3 | type: cloud-monitoring",
+			err: `unable to parse source "my-cloud-monitoring-instance" as "cloud-monitoring": [2:1] unknown field "project"
+   1 | kind: cloud-monitoring
+>  2 | project: test-project
+       ^
+`,
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-cloud-monitoring-instance
-			useClientOAuth: true
+			sources:
+				my-cloud-monitoring-instance:
+					useClientOAuth: true
 			`,
-			err: "error unmarshaling sources: missing 'type' field or it is not a string",
+			err: "missing 'kind' field for source \"my-cloud-monitoring-instance\"",
 		},
 	}
 	for _, tc := range tcs {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cloudsqladmin/cloud_sql_admin.go

@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"net/http"
 	"regexp"
+	"strconv"
 	"strings"
 	"text/template"
 	"time"
@@ -34,16 +35,19 @@ import (
 	sqladmin "google.golang.org/api/sqladmin/v1"
 )
 
-const SourceType string = "cloud-sql-admin"
+const SourceKind string = "cloud-sql-admin"
 
-var targetLinkRegex = regexp.MustCompile(`/projects/([^/]+)/instances/([^/]+)/databases/([^/]+)`)
+var (
+	targetLinkRegex = regexp.MustCompile(`/projects/([^/]+)/instances/([^/]+)/databases/([^/]+)`)
+	backupDRRegex   = regexp.MustCompile(`^projects/([^/]+)/locations/([^/]+)/backupVaults/([^/]+)/dataSources/([^/]+)/backups/([^/]+)$`)
+)
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -57,13 +61,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name           string `yaml:"name" validate:"required"`
-	Type           string `yaml:"type" validate:"required"`
+	Kind           string `yaml:"kind" validate:"required"`
 	DefaultProject string `yaml:"defaultProject"`
 	UseClientOAuth bool   `yaml:"useClientOAuth"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize initializes a CloudSQL Admin Source instance.
@@ -110,8 +114,8 @@ type Source struct {
 	Service *sqladmin.Service
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -374,6 +378,48 @@ func (s *Source) InsertBackupRun(ctx context.Context, project, instance, locatio
 	return resp, nil
 }
 
+func (s *Source) RestoreBackup(ctx context.Context, targetProject, targetInstance, sourceProject, sourceInstance, backupID, accessToken string) (any, error) {
+	request := &sqladmin.InstancesRestoreBackupRequest{}
+
+	// There are 3 scenarios for the backup identifier:
+	// 1. The identifier is an int64 containing the timestamp of the BackupRun.
+	//    This is used to restore standard backups, and the RestoreBackupContext
+	//    field should be populated with the backup ID and source instance info.
+	// 2. The identifier is a string of the format
+	//    'projects/{project-id}/locations/{location}/backupVaults/{backupvault}/dataSources/{datasource}/backups/{backup-uid}'.
+	//    This is used to restore BackupDR backups, and the BackupdrBackup field
+	//    should be populated.
+	// 3. The identifer is a string of the format
+	//    'projects/{project-id}/backups/{backup-uid}'. In this case, the Backup
+	//    field should be populated.
+	if backupRunID, err := strconv.ParseInt(backupID, 10, 64); err == nil {
+		if sourceProject == "" || targetInstance == "" {
+			return nil, fmt.Errorf("source project and instance are required when restoring via backup ID")
+		}
+		request.RestoreBackupContext = &sqladmin.RestoreBackupContext{
+			Project:     sourceProject,
+			InstanceId:  sourceInstance,
+			BackupRunId: backupRunID,
+		}
+	} else if backupDRRegex.MatchString(backupID) {
+		request.BackupdrBackup = backupID
+	} else {
+		request.Backup = backupID
+	}
+
+	service, err := s.GetService(ctx, string(accessToken))
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := service.Instances.RestoreBackup(targetProject, targetInstance, request).Do()
+	if err != nil {
+		return nil, fmt.Errorf("error restoring backup: %w", err)
+	}
+
+	return resp, nil
+}
+
 func generateCloudSQLConnectionMessage(ctx context.Context, source *Source, logger log.Logger, opResponse map[string]any, connectionMessageTemplate string) (string, bool) {
 	operationType, ok := opResponse["operationType"].(string)
 	if !ok || operationType != "CREATE_DATABASE" {

internal/sources/cloudsqladmin/cloud_sql_admin_test.go

@@ -15,9 +15,9 @@
 package cloudsqladmin_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -35,14 +35,14 @@ func TestParseFromYamlCloudSQLAdmin(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-cloud-sql-admin-instance
-			type: cloud-sql-admin
+			sources:
+				my-cloud-sql-admin-instance:
+					kind: cloud-sql-admin
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-cloud-sql-admin-instance": cloudsqladmin.Config{
 					Name:           "my-cloud-sql-admin-instance",
-					Type:           cloudsqladmin.SourceType,
+					Kind:           cloudsqladmin.SourceKind,
 					UseClientOAuth: false,
 				},
 			},
@@ -50,15 +50,15 @@ func TestParseFromYamlCloudSQLAdmin(t *testing.T) {
 		{
 			desc: "use client auth example",
 			in: `
-			kind: sources
-			name: my-cloud-sql-admin-instance
-			type: cloud-sql-admin
-			useClientOAuth: true
+			sources:
+				my-cloud-sql-admin-instance:
+					kind: cloud-sql-admin
+					useClientOAuth: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-cloud-sql-admin-instance": cloudsqladmin.Config{
 					Name:           "my-cloud-sql-admin-instance",
-					Type:           cloudsqladmin.SourceType,
+					Kind:           cloudsqladmin.SourceKind,
 					UseClientOAuth: true,
 				},
 			},
@@ -68,12 +68,16 @@ func TestParseFromYamlCloudSQLAdmin(t *testing.T) {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -89,28 +93,36 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-cloud-sql-admin-instance
-			type: cloud-sql-admin
-			project: test-project
+			sources:
+				my-cloud-sql-admin-instance:
+					kind: cloud-sql-admin
+					project: test-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-cloud-sql-admin-instance\" as \"cloud-sql-admin\": [2:1] unknown field \"project\"\n   1 | name: my-cloud-sql-admin-instance\n>  2 | project: test-project\n       ^\n   3 | type: cloud-sql-admin",
+			err: `unable to parse source "my-cloud-sql-admin-instance" as "cloud-sql-admin": [2:1] unknown field "project"
+   1 | kind: cloud-sql-admin
+>  2 | project: test-project
+       ^
+`,
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-cloud-sql-admin-instance
-			useClientOAuth: true
+			sources:
+				my-cloud-sql-admin-instance:
+					useClientOAuth: true
 			`,
-			err: "error unmarshaling sources: missing 'type' field or it is not a string",
+			err: "missing 'kind' field for source \"my-cloud-sql-admin-instance\"",
 		},
 	}
 	for _, tc := range tcs {
 		tc := tc
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cloudsqlmssql/cloud_sql_mssql.go

@@ -29,14 +29,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "cloud-sql-mssql"
+const SourceKind string = "cloud-sql-mssql"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,7 +51,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// Cloud SQL MSSQL configs
 	Name      string         `yaml:"name" validate:"required"`
-	Type      string         `yaml:"type" validate:"required"`
+	Kind      string         `yaml:"kind" validate:"required"`
 	Project   string         `yaml:"project" validate:"required"`
 	Region    string         `yaml:"region" validate:"required"`
 	Instance  string         `yaml:"instance" validate:"required"`
@@ -62,9 +62,9 @@ type Config struct {
 	Database  string         `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	// Returns Cloud SQL MSSQL source type
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	// Returns Cloud SQL MSSQL source kind
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -94,9 +94,9 @@ type Source struct {
 	Db *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	// Returns Cloud SQL MSSQL source type
-	return SourceType
+func (s *Source) SourceKind() string {
+	// Returns Cloud SQL MSSQL source kind
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -152,7 +152,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initCloudSQLMssqlConnection(ctx context.Context, tracer trace.Tracer, name, project, region, instance, ipType, user, pass, dbname string) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)

internal/sources/cloudsqlmssql/cloud_sql_mssql_test.go

@@ -15,12 +15,11 @@
 package cloudsqlmssql_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/cloudsqlmssql"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,20 +33,20 @@ func TestParseFromYamlCloudSQLMssql(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudsqlmssql.Config{
 					Name:     "my-instance",
-					Type:     cloudsqlmssql.SourceType,
+					Kind:     cloudsqlmssql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -61,21 +60,21 @@ func TestParseFromYamlCloudSQLMssql(t *testing.T) {
 		{
 			desc: "psc ipType",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
-			ipType: psc
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
+					ipType: psc
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudsqlmssql.Config{
 					Name:     "my-instance",
-					Type:     cloudsqlmssql.SourceType,
+					Kind:     cloudsqlmssql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -89,21 +88,21 @@ func TestParseFromYamlCloudSQLMssql(t *testing.T) {
 		{
 			desc: "with deprecated ipAddress",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipAddress: random
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipAddress: random
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": cloudsqlmssql.Config{
 					Name:      "my-instance",
-					Type:      cloudsqlmssql.SourceType,
+					Kind:      cloudsqlmssql.SourceKind,
 					Project:   "my-project",
 					Region:    "my-region",
 					Instance:  "my-instance",
@@ -118,12 +117,16 @@ func TestParseFromYamlCloudSQLMssql(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect psarse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect psarse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -139,53 +142,57 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "invalid ipType",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: fail
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: fail
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"cloud-sql-mssql\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
+			err: "unable to parse source \"my-instance\" as \"cloud-sql-mssql\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
 		},
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"cloud-sql-mssql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | name: my-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-instance\" as \"cloud-sql-mssql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | kind: cloud-sql-mssql\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: cloud-sql-mssql
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-instance:
+					kind: cloud-sql-mssql
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"cloud-sql-mssql\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-instance\" as \"cloud-sql-mssql\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cloudsqlmysql/cloud_sql_mysql.go

@@ -30,14 +30,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "cloud-sql-mysql"
+const SourceKind string = "cloud-sql-mysql"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,7 +51,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string         `yaml:"name" validate:"required"`
-	Type     string         `yaml:"type" validate:"required"`
+	Kind     string         `yaml:"kind" validate:"required"`
 	Project  string         `yaml:"project" validate:"required"`
 	Region   string         `yaml:"region" validate:"required"`
 	Instance string         `yaml:"instance" validate:"required"`
@@ -61,8 +61,8 @@ type Config struct {
 	Database string         `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -90,8 +90,8 @@ type Source struct {
 	Pool *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -184,7 +184,7 @@ func getConnectionConfig(ctx context.Context, user, pass string) (string, string
 
 func initCloudSQLMySQLConnectionPool(ctx context.Context, tracer trace.Tracer, name, project, region, instance, ipType, user, pass, dbname string) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Configure the driver to connect to the database

internal/sources/cloudsqlmysql/cloud_sql_mysql_test.go

@@ -15,12 +15,11 @@
 package cloudsqlmysql_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/cloudsqlmysql"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,20 +33,20 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": cloudsqlmysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     cloudsqlmysql.SourceType,
+					Kind:     cloudsqlmysql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -61,21 +60,21 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "public ipType",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: Public
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: Public
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": cloudsqlmysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     cloudsqlmysql.SourceType,
+					Kind:     cloudsqlmysql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -89,21 +88,21 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "private ipType",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: private
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: private 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": cloudsqlmysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     cloudsqlmysql.SourceType,
+					Kind:     cloudsqlmysql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -117,21 +116,21 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "psc ipType",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: psc
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: psc
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": cloudsqlmysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     cloudsqlmysql.SourceType,
+					Kind:     cloudsqlmysql.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -145,12 +144,16 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -166,53 +169,57 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "invalid ipType",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: fail
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: fail 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
+			err: "unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
 		},
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | name: my-mysql-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | kind: cloud-sql-mysql\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: cloud-sql-mysql
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: cloud-sql-mysql
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-mysql-instance\" as \"cloud-sql-mysql\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/cloudsqlpg/cloud_sql_pg.go

@@ -28,14 +28,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "cloud-sql-postgres"
+const SourceKind string = "cloud-sql-postgres"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -49,7 +49,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string         `yaml:"name" validate:"required"`
-	Type     string         `yaml:"type" validate:"required"`
+	Kind     string         `yaml:"kind" validate:"required"`
 	Project  string         `yaml:"project" validate:"required"`
 	Region   string         `yaml:"region" validate:"required"`
 	Instance string         `yaml:"instance" validate:"required"`
@@ -59,8 +59,8 @@ type Config struct {
 	Password string         `yaml:"password"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -88,8 +88,8 @@ type Source struct {
 	Pool *pgxpool.Pool
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -162,7 +162,7 @@ func getConnectionConfig(ctx context.Context, user, pass, dbname string) (string
 
 func initCloudSQLPgConnectionPool(ctx context.Context, tracer trace.Tracer, name, project, region, instance, ipType, user, pass, dbname string) (*pgxpool.Pool, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Configure the driver to connect to the database

internal/sources/cloudsqlpg/cloud_sql_pg_test.go

@@ -15,12 +15,11 @@
 package cloudsqlpg_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/cloudsqlpg"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,20 +33,20 @@ func TestParseFromYamlCloudSQLPg(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": cloudsqlpg.Config{
 					Name:     "my-pg-instance",
-					Type:     cloudsqlpg.SourceType,
+					Kind:     cloudsqlpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -61,21 +60,21 @@ func TestParseFromYamlCloudSQLPg(t *testing.T) {
 		{
 			desc: "public ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: Public
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: Public
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": cloudsqlpg.Config{
 					Name:     "my-pg-instance",
-					Type:     cloudsqlpg.SourceType,
+					Kind:     cloudsqlpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -89,21 +88,21 @@ func TestParseFromYamlCloudSQLPg(t *testing.T) {
 		{
 			desc: "private ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: private 
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: private 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": cloudsqlpg.Config{
 					Name:     "my-pg-instance",
-					Type:     cloudsqlpg.SourceType,
+					Kind:     cloudsqlpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -117,21 +116,21 @@ func TestParseFromYamlCloudSQLPg(t *testing.T) {
 		{
 			desc: "psc ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: psc 
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: psc 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": cloudsqlpg.Config{
 					Name:     "my-pg-instance",
-					Type:     cloudsqlpg.SourceType,
+					Kind:     cloudsqlpg.SourceKind,
 					Project:  "my-project",
 					Region:   "my-region",
 					Instance: "my-instance",
@@ -145,12 +144,16 @@ func TestParseFromYamlCloudSQLPg(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -166,53 +169,57 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "invalid ipType",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			ipType: fail 
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					ipType: fail 
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
+			err: "unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": ipType invalid: must be one of \"public\", \"private\", or \"psc\"",
 		},
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			project: my-project
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					project: my-project
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | name: my-pg-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | instance: my-instance\n   4 | kind: cloud-sql-postgres\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: cloud-sql-postgres
-			region: my-region
-			instance: my-instance
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: cloud-sql-postgres
+					region: my-region
+					instance: my-instance
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-pg-instance\" as \"cloud-sql-postgres\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/couchbase/couchbase.go

@@ -29,14 +29,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "couchbase"
+const SourceKind string = "couchbase"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,7 +50,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name                 string `yaml:"name" validate:"required"`
-	Type                 string `yaml:"type" validate:"required"`
+	Kind                 string `yaml:"kind" validate:"required"`
 	ConnectionString     string `yaml:"connectionString" validate:"required"`
 	Bucket               string `yaml:"bucket" validate:"required"`
 	Scope                string `yaml:"scope" validate:"required"`
@@ -66,8 +66,8 @@ type Config struct {
 	QueryScanConsistency uint   `yaml:"queryScanConsistency"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -96,8 +96,8 @@ type Source struct {
 	Scope *gocb.Scope
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/couchbase/couchbase_test.go

@@ -15,12 +15,11 @@
 package couchbase_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/couchbase"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlCouchbase(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-couchbase-instance
-			type: couchbase
-			connectionString: localhost
-			username: Administrator
-			password: password
-			bucket: travel-sample
-			scope: inventory
+			sources:
+				my-couchbase-instance:
+					kind: couchbase
+					connectionString: localhost
+					username: Administrator
+					password: password
+					bucket: travel-sample
+					scope: inventory
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-couchbase-instance": couchbase.Config{
 					Name:             "my-couchbase-instance",
-					Type:             couchbase.SourceType,
+					Kind:             couchbase.SourceKind,
 					ConnectionString: "localhost",
 					Username:         "Administrator",
 					Password:         "password",
@@ -58,24 +57,24 @@ func TestParseFromYamlCouchbase(t *testing.T) {
 		{
 			desc: "with TLS configuration",
 			in: `
-			kind: sources
-			name: my-couchbase-instance
-			type: couchbase
-			connectionString: couchbases://localhost
-			bucket: travel-sample
-			scope: inventory
-			clientCert: /path/to/cert.pem
-			clientKey: /path/to/key.pem
-			clientCertPassword: password
-			clientKeyPassword: password
-			caCert: /path/to/ca.pem
-			noSslVerify: false
-			queryScanConsistency: 2
+			sources:
+				my-couchbase-instance:
+					kind: couchbase
+					connectionString: couchbases://localhost
+					bucket: travel-sample
+					scope: inventory
+					clientCert: /path/to/cert.pem
+					clientKey: /path/to/key.pem
+					clientCertPassword: password
+					clientKeyPassword: password
+					caCert: /path/to/ca.pem
+					noSslVerify: false
+					queryScanConsistency: 2
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-couchbase-instance": couchbase.Config{
 					Name:                 "my-couchbase-instance",
-					Type:                 couchbase.SourceType,
+					Kind:                 couchbase.SourceKind,
 					ConnectionString:     "couchbases://localhost",
 					Bucket:               "travel-sample",
 					Scope:                "inventory",
@@ -92,12 +91,16 @@ func TestParseFromYamlCouchbase(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -112,35 +115,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-couchbase-instance
-			type: couchbase
-			connectionString: localhost
-			username: Administrator
-			password: password
-			bucket: travel-sample
-			scope: inventory
-			foo: bar
+			sources:
+				my-couchbase-instance:
+					kind: couchbase
+					connectionString: localhost
+					username: Administrator
+					password: password
+					bucket: travel-sample
+					scope: inventory
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-couchbase-instance\" as \"couchbase\": [3:1] unknown field \"foo\"\n   1 | bucket: travel-sample\n   2 | connectionString: localhost\n>  3 | foo: bar\n       ^\n   4 | name: my-couchbase-instance\n   5 | password: password\n   6 | scope: inventory\n   7 | ",
+			err: "unable to parse source \"my-couchbase-instance\" as \"couchbase\": [3:1] unknown field \"foo\"\n   1 | bucket: travel-sample\n   2 | connectionString: localhost\n>  3 | foo: bar\n       ^\n   4 | kind: couchbase\n   5 | password: password\n   6 | scope: inventory\n   7 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-couchbase-instance
-			type: couchbase
-			username: Administrator
-			password: password
-			bucket: travel-sample
-			scope: inventory
+			sources:
+				my-couchbase-instance:
+					kind: couchbase
+					username: Administrator
+					password: password
+					bucket: travel-sample
+					scope: inventory
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-couchbase-instance\" as \"couchbase\": Key: 'Config.ConnectionString' Error:Field validation for 'ConnectionString' failed on the 'required' tag",
+			err: "unable to parse source \"my-couchbase-instance\" as \"couchbase\": Key: 'Config.ConnectionString' Error:Field validation for 'ConnectionString' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/dataplex/dataplex.go

@@ -29,14 +29,14 @@ import (
 	"google.golang.org/api/option"
 )
 
-const SourceType string = "dataplex"
+const SourceKind string = "dataplex"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,13 +51,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// Dataplex configs
 	Name    string `yaml:"name" validate:"required"`
-	Type    string `yaml:"type" validate:"required"`
+	Kind    string `yaml:"kind" validate:"required"`
 	Project string `yaml:"project" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	// Returns Dataplex source type
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	// Returns Dataplex source kind
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -81,9 +81,9 @@ type Source struct {
 	Client *dataplexapi.CatalogClient
 }
 
-func (s *Source) SourceType() string {
-	// Returns Dataplex source type
-	return SourceType
+func (s *Source) SourceKind() string {
+	// Returns Dataplex source kind
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -104,7 +104,7 @@ func initDataplexConnection(
 	name string,
 	project string,
 ) (*dataplexapi.CatalogClient, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	cred, err := google.FindDefaultCredentials(ctx)

internal/sources/dataplex/dataplex_test.go

@@ -15,12 +15,11 @@
 package dataplex_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/dataplex"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,15 +33,15 @@ func TestParseFromYamlDataplex(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-instance
-			type: dataplex
-			project: my-project
+			sources:
+				my-instance:
+					kind: dataplex
+					project: my-project
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": dataplex.Config{
 					Name:    "my-instance",
-					Type:    dataplex.SourceType,
+					Kind:    dataplex.SourceKind,
 					Project: "my-project",
 				},
 			},
@@ -50,12 +49,16 @@ func TestParseFromYamlDataplex(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -71,27 +74,31 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: dataplex
-			project: my-project
-			foo: bar
+			sources:
+				my-instance:
+					kind: dataplex
+					project: my-project
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"dataplex\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | name: my-instance\n   3 | project: my-project\n   4 | type: dataplex",
+			err: "unable to parse source \"my-instance\" as \"dataplex\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | kind: dataplex\n   3 | project: my-project",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-instance
-			type: dataplex
+			sources:
+				my-instance:
+					kind: dataplex
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"dataplex\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-instance\" as \"dataplex\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/dgraph/dgraph.go

@@ -30,14 +30,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "dgraph"
+const SourceKind string = "dgraph"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -67,7 +67,7 @@ type DgraphClient struct {
 
 type Config struct {
 	Name      string `yaml:"name" validate:"required"`
-	Type      string `yaml:"type" validate:"required"`
+	Kind      string `yaml:"kind" validate:"required"`
 	DgraphUrl string `yaml:"dgraphUrl" validate:"required"`
 	User      string `yaml:"user"`
 	Password  string `yaml:"password"`
@@ -75,8 +75,8 @@ type Config struct {
 	ApiKey    string `yaml:"apiKey"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -103,8 +103,8 @@ type Source struct {
 	Client *DgraphClient `yaml:"client"`
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -139,7 +139,7 @@ func (s *Source) RunSQL(statement string, params parameters.ParamValues, isQuery
 
 func initDgraphHttpClient(ctx context.Context, tracer trace.Tracer, r Config) (*DgraphClient, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, r.Name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, r.Name)
 	defer span.End()
 
 	if r.DgraphUrl == "" {

internal/sources/dgraph/dgraph_test.go

@@ -15,12 +15,11 @@
 package dgraph_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/dgraph"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlDgraph(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-dgraph-instance
-			type: dgraph
-			dgraphUrl: https://localhost:8080
-			apiKey: abc123
-			password: pass@123
-			namespace: 0
-			user: user123
+			sources:
+				my-dgraph-instance:
+					kind: dgraph
+					dgraphUrl: https://localhost:8080
+					apiKey: abc123
+					password: pass@123
+					namespace: 0
+					user: user123
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-dgraph-instance": dgraph.Config{
 					Name:      "my-dgraph-instance",
-					Type:      dgraph.SourceType,
+					Kind:      dgraph.SourceKind,
 					DgraphUrl: "https://localhost:8080",
 					ApiKey:    "abc123",
 					Password:  "pass@123",
@@ -58,15 +57,15 @@ func TestParseFromYamlDgraph(t *testing.T) {
 		{
 			desc: "basic example minimal field",
 			in: `
-			kind: sources
-			name: my-dgraph-instance
-			type: dgraph
-			dgraphUrl: https://localhost:8080
+			sources:
+				my-dgraph-instance:
+					kind: dgraph
+					dgraphUrl: https://localhost:8080
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-dgraph-instance": dgraph.Config{
 					Name:      "my-dgraph-instance",
-					Type:      dgraph.SourceType,
+					Kind:      dgraph.SourceKind,
 					DgraphUrl: "https://localhost:8080",
 				},
 			},
@@ -75,12 +74,16 @@ func TestParseFromYamlDgraph(t *testing.T) {
 
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
 
-			if diff := cmp.Diff(tc.want, got); diff != "" {
+			if diff := cmp.Diff(tc.want, got.Sources); diff != "" {
 				t.Fatalf("incorrect parse: diff %v", diff)
 			}
 		})
@@ -97,27 +100,31 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-dgraph-instance
-			type: dgraph
-			dgraphUrl: https://localhost:8080
-			foo: bar
+			sources:
+				my-dgraph-instance:
+					kind: dgraph
+					dgraphUrl: https://localhost:8080
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-dgraph-instance\" as \"dgraph\": [2:1] unknown field \"foo\"\n   1 | dgraphUrl: https://localhost:8080\n>  2 | foo: bar\n       ^\n   3 | name: my-dgraph-instance\n   4 | type: dgraph",
+			err: "unable to parse source \"my-dgraph-instance\" as \"dgraph\": [2:1] unknown field \"foo\"\n   1 | dgraphUrl: https://localhost:8080\n>  2 | foo: bar\n       ^\n   3 | kind: dgraph",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-dgraph-instance
-			type: dgraph
+			sources:
+				my-dgraph-instance:
+					kind: dgraph
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-dgraph-instance\" as \"dgraph\": Key: 'Config.DgraphUrl' Error:Field validation for 'DgraphUrl' failed on the 'required' tag",
+			err: "unable to parse source \"my-dgraph-instance\" as \"dgraph\": Key: 'Config.DgraphUrl' Error:Field validation for 'DgraphUrl' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/elasticsearch/elasticsearch.go

@@ -30,14 +30,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "elasticsearch"
+const SourceKind string = "elasticsearch"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,15 +51,15 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name      string   `yaml:"name" validate:"required"`
-	Type      string   `yaml:"type" validate:"required"`
+	Kind      string   `yaml:"kind" validate:"required"`
 	Addresses []string `yaml:"addresses" validate:"required"`
 	Username  string   `yaml:"username"`
 	Password  string   `yaml:"password"`
 	APIKey    string   `yaml:"apikey"`
 }
 
-func (c Config) SourceConfigType() string {
-	return SourceType
+func (c Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 type EsClient interface {
@@ -139,9 +139,9 @@ func (c Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.So
 	return s, nil
 }
 
-// SourceType returns the resourceType string for this source.
-func (s *Source) SourceType() string {
-	return SourceType
+// SourceKind returns the kind string for this source.
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/elasticsearch/elasticsearch_test.go

@@ -15,15 +15,13 @@
 package elasticsearch_test
 
 import (
-	"context"
 	"reflect"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/elasticsearch"
-	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
 
 func TestParseFromYamlElasticsearch(t *testing.T) {
@@ -35,17 +33,17 @@ func TestParseFromYamlElasticsearch(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-es-instance
-			type: elasticsearch
-			addresses:
-				- http://localhost:9200
-			apikey: somekey
-			`,
-			want: map[string]sources.SourceConfig{
+            sources:
+              my-es-instance:
+                kind: elasticsearch
+                addresses:
+                  - http://localhost:9200
+                apikey: somekey
+            `,
+			want: server.SourceConfigs{
 				"my-es-instance": elasticsearch.Config{
 					Name:      "my-es-instance",
-					Type:      elasticsearch.SourceType,
+					Kind:      elasticsearch.SourceKind,
 					Addresses: []string{"http://localhost:9200"},
 					APIKey:    "somekey",
 				},
@@ -54,50 +52,20 @@ func TestParseFromYamlElasticsearch(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			err := yaml.Unmarshal([]byte(tc.in), &got)
 			if err != nil {
 				t.Fatalf("failed to parse yaml: %v", err)
 			}
-			if diff := cmp.Diff(tc.want, got); diff != "" {
+			if diff := cmp.Diff(tc.want, got.Sources); diff != "" {
 				t.Errorf("unexpected config diff (-want +got):\n%s", diff)
 			}
 		})
 	}
 }
 
-func TestFailParseFromYaml(t *testing.T) {
-	tcs := []struct {
-		desc string
-		in   string
-		err  string
-	}{
-		{
-			desc: "extra field",
-			in: `
-			kind: sources
-			name: my-es-instance
-			type: elasticsearch
-			addresses:
-				- http://localhost:9200
-			foo: bar
-			`,
-			err: "error unmarshaling sources: unable to parse source \"my-es-instance\" as \"elasticsearch\": [3:1] unknown field \"foo\"\n   1 | addresses:\n   2 | - http://localhost:9200\n>  3 | foo: bar\n       ^\n   4 | name: my-es-instance\n   5 | type: elasticsearch",
-		},
-	}
-	for _, tc := range tcs {
-		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
-			if err == nil {
-				t.Fatalf("expect parsing to fail")
-			}
-			errStr := err.Error()
-			if errStr != tc.err {
-				t.Fatalf("unexpected error: got %q, want %q", errStr, tc.err)
-			}
-		})
-	}
-}
-
 func TestTool_esqlToMap(t1 *testing.T) {
 	tests := []struct {
 		name   string

internal/sources/firebird/firebird.go

@@ -27,13 +27,13 @@ import (
 	"github.com/googleapis/genai-toolbox/internal/sources"
 )
 
-const SourceType string = "firebird"
+const SourceKind string = "firebird"
 
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -47,7 +47,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Host     string `yaml:"host" validate:"required"`
 	Port     string `yaml:"port" validate:"required"`
 	User     string `yaml:"user" validate:"required"`
@@ -55,8 +55,8 @@ type Config struct {
 	Database string `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -84,8 +84,8 @@ type Source struct {
 	Db *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -144,7 +144,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 }
 
 func initFirebirdConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname string) (*sql.DB, error) {
-	_, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	_, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// urlExample := "user:password@host:port/path/to/database.fdb"

internal/sources/firebird/firebird_test.go

@@ -15,12 +15,11 @@
 package firebird_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/firebird"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlFirebird(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-fdb-instance
-			type: firebird
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-fdb-instance:
+					kind: firebird
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-fdb-instance": firebird.Config{
 					Name:     "my-fdb-instance",
-					Type:     firebird.SourceType,
+					Kind:     firebird.SourceKind,
 					Host:     "my-host",
 					Port:     "my-port",
 					Database: "my_db",
@@ -58,12 +57,16 @@ func TestParseFromYamlFirebird(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -79,35 +82,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-fdb-instance
-			type: firebird
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-fdb-instance:
+					kind: firebird
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-fdb-instance\" as \"firebird\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: my-host\n   4 | name: my-fdb-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-fdb-instance\" as \"firebird\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: my-host\n   4 | kind: firebird\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-fdb-instance
-			type: firebird
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
+			sources:
+				my-fdb-instance:
+					kind: firebird
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-fdb-instance\" as \"firebird\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
+			err: "unable to parse source \"my-fdb-instance\" as \"firebird\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/firestore/firestore.go

@@ -31,14 +31,14 @@ import (
 	"google.golang.org/genproto/googleapis/type/latlng"
 )
 
-const SourceType string = "firestore"
+const SourceKind string = "firestore"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -53,14 +53,14 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// Firestore configs
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Project  string `yaml:"project" validate:"required"`
 	Database string `yaml:"database"` // Optional, defaults to "(default)"
 }
 
-func (r Config) SourceConfigType() string {
-	// Returns Firestore source type
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	// Returns Firestore source kind
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -92,9 +92,9 @@ type Source struct {
 	RulesClient *firebaserules.Service
 }
 
-func (s *Source) SourceType() string {
-	// Returns Firestore source type
-	return SourceType
+func (s *Source) SourceKind() string {
+	// Returns Firestore source kind
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -594,7 +594,7 @@ func initFirestoreConnection(
 	project string,
 	database string,
 ) (*firestore.Client, error) {
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)

internal/sources/firestore/firestore_test.go

@@ -15,13 +15,12 @@
 package firestore_test
 
 import (
-	"context"
 	"testing"
 	"time"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/firestore"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -35,15 +34,15 @@ func TestParseFromYamlFirestore(t *testing.T) {
 		{
 			desc: "basic example with default database",
 			in: `
-			kind: sources
-			name: my-firestore
-			type: firestore
-			project: my-project
+			sources:
+				my-firestore:
+					kind: firestore
+					project: my-project
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-firestore": firestore.Config{
 					Name:     "my-firestore",
-					Type:     firestore.SourceType,
+					Kind:     firestore.SourceKind,
 					Project:  "my-project",
 					Database: "",
 				},
@@ -52,16 +51,16 @@ func TestParseFromYamlFirestore(t *testing.T) {
 		{
 			desc: "with custom database",
 			in: `
-			kind: sources
-			name: my-firestore
-			type: firestore
-			project: my-project
-			database: my-database
+			sources:
+				my-firestore:
+					kind: firestore
+					project: my-project
+					database: my-database
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-firestore": firestore.Config{
 					Name:     "my-firestore",
-					Type:     firestore.SourceType,
+					Kind:     firestore.SourceKind,
 					Project:  "my-project",
 					Database: "my-database",
 				},
@@ -70,18 +69,22 @@ func TestParseFromYamlFirestore(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
 }
 
-func TestFailParseFromYaml(t *testing.T) {
+func TestFailParseFromYamlFirestore(t *testing.T) {
 	tcs := []struct {
 		desc string
 		in   string
@@ -90,27 +93,32 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-firestore
-			type: firestore
-			project: my-project
-			foo: bar
+			sources:
+				my-firestore:
+					kind: firestore
+					project: my-project
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-firestore\" as \"firestore\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | name: my-firestore\n   3 | project: my-project\n   4 | type: firestore",
+			err: "unable to parse source \"my-firestore\" as \"firestore\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | kind: firestore\n   3 | project: my-project",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-firestore
-			type: firestore
+			sources:
+				my-firestore:
+					kind: firestore
+					database: my-database
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-firestore\" as \"firestore\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-firestore\" as \"firestore\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/http/http.go

@@ -29,14 +29,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "http"
+const SourceKind string = "http"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,7 +50,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name                   string            `yaml:"name" validate:"required"`
-	Type                   string            `yaml:"type" validate:"required"`
+	Kind                   string            `yaml:"kind" validate:"required"`
 	BaseURL                string            `yaml:"baseUrl"`
 	Timeout                string            `yaml:"timeout"`
 	DefaultHeaders         map[string]string `yaml:"headers"`
@@ -58,8 +58,8 @@ type Config struct {
 	DisableSslVerification bool              `yaml:"disableSslVerification"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize initializes an HTTP Source instance.
@@ -122,8 +122,8 @@ type Source struct {
 	client *http.Client
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/http/http_test.go

@@ -15,9 +15,9 @@
 package http_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -34,15 +34,15 @@ func TestParseFromYamlHttp(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-http-instance
-			type: http
-			baseUrl: http://test_server/
+			sources:
+				my-http-instance:
+					kind: http
+					baseUrl: http://test_server/
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-http-instance": http.Config{
 					Name:                   "my-http-instance",
-					Type:                   http.SourceType,
+					Kind:                   http.SourceKind,
 					BaseURL:                "http://test_server/",
 					Timeout:                "30s",
 					DisableSslVerification: false,
@@ -52,23 +52,23 @@ func TestParseFromYamlHttp(t *testing.T) {
 		{
 			desc: "advanced example",
 			in: `
-			kind: sources
-			name: my-http-instance
-			type: http
-			baseUrl: http://test_server/
-			timeout: 10s
-			headers:
-				Authorization: test_header
-				Custom-Header: custom
-			queryParams:
-				api-key: test_api_key
-				param: param-value
-			disableSslVerification: true
+			sources:
+				my-http-instance:
+					kind: http
+					baseUrl: http://test_server/
+					timeout: 10s
+					headers:
+						Authorization: test_header
+						Custom-Header: custom
+					queryParams:
+						api-key: test_api_key
+						param: param-value
+					disableSslVerification: true
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-http-instance": http.Config{
 					Name:                   "my-http-instance",
-					Type:                   http.SourceType,
+					Kind:                   http.SourceKind,
 					BaseURL:                "http://test_server/",
 					Timeout:                "10s",
 					DefaultHeaders:         map[string]string{"Authorization": "test_header", "Custom-Header": "custom"},
@@ -80,12 +80,16 @@ func TestParseFromYamlHttp(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -100,32 +104,36 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-http-instance
-			type: http
-			baseUrl: http://test_server/
-			timeout: 10s
-			headers:
-				Authorization: test_header
-			queryParams:
-				api-key: test_api_key
-			project: test-project
+			sources:
+				my-http-instance:
+					kind: http
+					baseUrl: http://test_server/
+					timeout: 10s
+					headers:
+						Authorization: test_header
+					queryParams:
+						api-key: test_api_key
+					project: test-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-http-instance\" as \"http\": [5:1] unknown field \"project\"\n   2 | headers:\n   3 |   Authorization: test_header\n   4 | name: my-http-instance\n>  5 | project: test-project\n       ^\n   6 | queryParams:\n   7 |   api-key: test_api_key\n   8 | timeout: 10s\n   9 | ",
+			err: "unable to parse source \"my-http-instance\" as \"http\": [5:1] unknown field \"project\"\n   2 | headers:\n   3 |   Authorization: test_header\n   4 | kind: http\n>  5 | project: test-project\n       ^\n   6 | queryParams:\n   7 |   api-key: test_api_key\n   8 | timeout: 10s",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-http-instance
-			baseUrl: http://test_server/
+			sources:
+				my-http-instance:
+					baseUrl: http://test_server/
 			`,
-			err: "error unmarshaling sources: missing 'type' field or it is not a string",
+			err: "missing 'kind' field for source \"my-http-instance\"",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/looker/looker.go

@@ -33,14 +33,14 @@ import (
 	v4 "github.com/looker-open-source/sdk-codegen/go/sdk/v4"
 )
 
-const SourceType string = "looker"
+const SourceKind string = "looker"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -64,7 +64,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name               string `yaml:"name" validate:"required"`
-	Type               string `yaml:"type" validate:"required"`
+	Kind               string `yaml:"kind" validate:"required"`
 	BaseURL            string `yaml:"base_url" validate:"required"`
 	ClientId           string `yaml:"client_id"`
 	ClientSecret       string `yaml:"client_secret"`
@@ -79,8 +79,8 @@ type Config struct {
 	SessionLength      int64  `yaml:"sessionLength"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize initializes a Looker Source instance.
@@ -154,8 +154,8 @@ type Source struct {
 	AuthTokenHeaderName string
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/looker/looker_test.go

@@ -15,9 +15,9 @@
 package looker_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
 	"github.com/googleapis/genai-toolbox/internal/sources"
@@ -34,17 +34,17 @@ func TestParseFromYamlLooker(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-looker-instance
-			type: looker
-			base_url: http://example.looker.com/
-			client_id: jasdl;k;tjl
-			client_secret: sdakl;jgflkasdfkfg
+			sources:
+				my-looker-instance:
+					kind: looker
+					base_url: http://example.looker.com/
+					client_id: jasdl;k;tjl
+					client_secret: sdakl;jgflkasdfkfg
 			`,
 			want: map[string]sources.SourceConfig{
 				"my-looker-instance": looker.Config{
 					Name:               "my-looker-instance",
-					Type:               looker.SourceType,
+					Kind:               looker.SourceKind,
 					BaseURL:            "http://example.looker.com/",
 					ClientId:           "jasdl;k;tjl",
 					ClientSecret:       "sdakl;jgflkasdfkfg",
@@ -62,18 +62,22 @@ func TestParseFromYamlLooker(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
 }
 
-func TestFailParseFromYaml(t *testing.T) {
+func TestFailParseFromYamlLooker(t *testing.T) {
 	tcs := []struct {
 		desc string
 		in   string
@@ -82,30 +86,34 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-looker-instance
-			type: looker
-			base_url: http://example.looker.com/
-			client_id: jasdl;k;tjl
-			client_secret: sdakl;jgflkasdfkfg
-			schema: test-schema
+			sources:
+				my-looker-instance:
+					kind: looker
+					base_url: http://example.looker.com/
+					client_id: jasdl;k;tjl
+					client_secret: sdakl;jgflkasdfkfg
+					schema: test-schema
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-looker-instance\" as \"looker\": [5:1] unknown field \"schema\"\n   2 | client_id: jasdl;k;tjl\n   3 | client_secret: sdakl;jgflkasdfkfg\n   4 | name: my-looker-instance\n>  5 | schema: test-schema\n       ^\n   6 | type: looker",
+			err: "unable to parse source \"my-looker-instance\" as \"looker\": [5:1] unknown field \"schema\"\n   2 | client_id: jasdl;k;tjl\n   3 | client_secret: sdakl;jgflkasdfkfg\n   4 | kind: looker\n>  5 | schema: test-schema\n       ^\n",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-looker-instance
-			type: looker
-			client_id: jasdl;k;tjl
+			sources:
+				my-looker-instance:
+					kind: looker
+					client_id: jasdl;k;tjl
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-looker-instance\" as \"looker\": Key: 'Config.BaseURL' Error:Field validation for 'BaseURL' failed on the 'required' tag",
+			err: "unable to parse source \"my-looker-instance\" as \"looker\": Key: 'Config.BaseURL' Error:Field validation for 'BaseURL' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/mindsdb/mindsdb.go

@@ -27,14 +27,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "mindsdb"
+const SourceKind string = "mindsdb"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -48,7 +48,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name         string `yaml:"name" validate:"required"`
-	Type         string `yaml:"type" validate:"required"`
+	Kind         string `yaml:"kind" validate:"required"`
 	Host         string `yaml:"host" validate:"required"`
 	Port         string `yaml:"port" validate:"required"`
 	User         string `yaml:"user" validate:"required"`
@@ -57,8 +57,8 @@ type Config struct {
 	QueryTimeout string `yaml:"queryTimeout"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -86,8 +86,8 @@ type Source struct {
 	Pool *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -159,7 +159,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initMindsDBConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname, queryTimeout string) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Configure the driver to connect to the database

internal/sources/mindsdb/mindsdb_test.go

@@ -15,12 +15,11 @@
 package mindsdb_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/mindsdb"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlMindsDB(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-mindsdb-instance
-			type: mindsdb
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mindsdb-instance:
+					kind: mindsdb
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mindsdb-instance": mindsdb.Config{
 					Name:     "my-mindsdb-instance",
-					Type:     mindsdb.SourceType,
+					Kind:     mindsdb.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -58,20 +57,20 @@ func TestParseFromYamlMindsDB(t *testing.T) {
 		{
 			desc: "with query timeout",
 			in: `
-			kind: sources
-			name: my-mindsdb-instance
-			type: mindsdb
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryTimeout: 45s
+			sources:
+				my-mindsdb-instance:
+					kind: mindsdb
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryTimeout: 45s
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mindsdb-instance": mindsdb.Config{
 					Name:         "my-mindsdb-instance",
-					Type:         mindsdb.SourceType,
+					Kind:         mindsdb.SourceKind,
 					Host:         "0.0.0.0",
 					Port:         "my-port",
 					Database:     "my_db",
@@ -84,12 +83,16 @@ func TestParseFromYamlMindsDB(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -105,35 +108,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-mindsdb-instance
-			type: mindsdb
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-mindsdb-instance:
+					kind: mindsdb
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mindsdb-instance\" as \"mindsdb\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | name: my-mindsdb-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-mindsdb-instance\" as \"mindsdb\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | kind: mindsdb\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-mindsdb-instance
-			type: mindsdb
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mindsdb-instance:
+					kind: mindsdb
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mindsdb-instance\" as \"mindsdb\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
+			err: "unable to parse source \"my-mindsdb-instance\" as \"mindsdb\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/mongodb/mongodb.go

@@ -29,14 +29,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "mongodb"
+const SourceKind string = "mongodb"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,12 +50,12 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name string `yaml:"name" validate:"required"`
-	Type string `yaml:"type" validate:"required"`
+	Kind string `yaml:"kind" validate:"required"`
 	Uri  string `yaml:"uri" validate:"required"` // MongoDB Atlas connection URI
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -84,8 +84,8 @@ type Source struct {
 	Client *mongo.Client
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -293,7 +293,7 @@ func (s *Source) DeleteOne(ctx context.Context, filterString, database, collecti
 
 func initMongoDBClient(ctx context.Context, tracer trace.Tracer, name, uri string) (*mongo.Client, error) {
 	// Start a tracing span
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)

internal/sources/mongodb/mongodb_test.go

@@ -15,12 +15,11 @@
 package mongodb_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/mongodb"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,15 +33,15 @@ func TestParseFromYamlMongoDB(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: mongo-db
-			type: "mongodb"
-			uri: "mongodb+srv://username:password@host/dbname"
+			sources:
+				mongo-db:
+					kind: "mongodb"
+					uri: "mongodb+srv://username:password@host/dbname"
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"mongo-db": mongodb.Config{
 					Name: "mongo-db",
-					Type: mongodb.SourceType,
+					Kind: mongodb.SourceKind,
 					Uri:  "mongodb+srv://username:password@host/dbname",
 				},
 			},
@@ -50,12 +49,16 @@ func TestParseFromYamlMongoDB(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -71,27 +74,31 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: mongo-db
-			type: mongodb
-			uri: "mongodb+srv://username:password@host/dbname"
-			foo: bar
+			sources:
+				mongo-db:
+					kind: mongodb
+					uri: "mongodb+srv://username:password@host/dbname"
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"mongo-db\" as \"mongodb\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | name: mongo-db\n   3 | type: mongodb\n   4 | uri: mongodb+srv://username:password@host/dbname",
+			err: "unable to parse source \"mongo-db\" as \"mongodb\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | kind: mongodb\n   3 | uri: mongodb+srv://username:password@host/dbname",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: mongo-db
-			type: mongodb
+			sources:
+				mongo-db:
+					kind: mongodb
 			`,
-			err: "error unmarshaling sources: unable to parse source \"mongo-db\" as \"mongodb\": Key: 'Config.Uri' Error:Field validation for 'Uri' failed on the 'required' tag",
+			err: "unable to parse source \"mongo-db\" as \"mongodb\": Key: 'Config.Uri' Error:Field validation for 'Uri' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/mssql/mssql.go

@@ -28,14 +28,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "mssql"
+const SourceKind string = "mssql"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -50,7 +50,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 type Config struct {
 	// Cloud SQL MSSQL configs
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Host     string `yaml:"host" validate:"required"`
 	Port     string `yaml:"port" validate:"required"`
 	User     string `yaml:"user" validate:"required"`
@@ -59,9 +59,9 @@ type Config struct {
 	Encrypt  string `yaml:"encrypt"`
 }
 
-func (r Config) SourceConfigType() string {
-	// Returns Cloud SQL MSSQL source type
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	// Returns Cloud SQL MSSQL source kind
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -91,9 +91,9 @@ type Source struct {
 	Db *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	// Returns Cloud SQL MSSQL source type
-	return SourceType
+func (s *Source) SourceKind() string {
+	// Returns Cloud SQL MSSQL source kind
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -156,7 +156,7 @@ func initMssqlConnection(
 	error,
 ) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	userAgent, err := util.UserAgentFromContext(ctx)

internal/sources/mssql/mssql_test.go

@@ -15,12 +15,11 @@
 package mssql_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/mssql"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlMssql(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-mssql-instance
-			type: mssql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mssql-instance:
+					kind: mssql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mssql-instance": mssql.Config{
 					Name:     "my-mssql-instance",
-					Type:     mssql.SourceType,
+					Kind:     mssql.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -58,20 +57,20 @@ func TestParseFromYamlMssql(t *testing.T) {
 		{
 			desc: "with encrypt field",
 			in: `
-			kind: sources
-			name: my-mssql-instance
-			type: mssql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			encrypt: strict
+			sources:
+				my-mssql-instance:
+					kind: mssql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					encrypt: strict
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mssql-instance": mssql.Config{
 					Name:     "my-mssql-instance",
-					Type:     mssql.SourceType,
+					Kind:     mssql.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -84,12 +83,16 @@ func TestParseFromYamlMssql(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect psarse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect psarse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -104,35 +107,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-mssql-instance
-			type: mssql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-mssql-instance:
+					kind: mssql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mssql-instance\" as \"mssql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | name: my-mssql-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-mssql-instance\" as \"mssql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | kind: mssql\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-mssql-instance
-			type: mssql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
+			sources:
+				my-mssql-instance:
+					kind: mssql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mssql-instance\" as \"mssql\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
+			err: "unable to parse source \"my-mssql-instance\" as \"mssql\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/mysql/mysql.go

@@ -30,14 +30,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "mysql"
+const SourceKind string = "mysql"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -51,7 +51,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name         string            `yaml:"name" validate:"required"`
-	Type         string            `yaml:"type" validate:"required"`
+	Kind         string            `yaml:"kind" validate:"required"`
 	Host         string            `yaml:"host" validate:"required"`
 	Port         string            `yaml:"port" validate:"required"`
 	User         string            `yaml:"user" validate:"required"`
@@ -61,8 +61,8 @@ type Config struct {
 	QueryParams  map[string]string `yaml:"queryParams"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -90,8 +90,8 @@ type Source struct {
 	Pool *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -158,7 +158,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initMySQLConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname, queryTimeout string, queryParams map[string]string) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Build query parameters via url.Values for deterministic order and proper escaping.

internal/sources/mysql/mysql_test.go

@@ -19,12 +19,12 @@ import (
 	"strings"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"go.opentelemetry.io/otel/trace/noop"
 
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/mysql"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -38,19 +38,19 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": mysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     mysql.SourceType,
+					Kind:     mysql.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -62,20 +62,20 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "with query timeout",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryTimeout: 45s
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryTimeout: 45s
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": mysql.Config{
 					Name:         "my-mysql-instance",
-					Type:         mysql.SourceType,
+					Kind:         mysql.SourceKind,
 					Host:         "0.0.0.0",
 					Port:         "my-port",
 					Database:     "my_db",
@@ -88,22 +88,22 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 		{
 			desc: "with query params",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryParams:
-				tls: preferred
-				charset: utf8mb4
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryParams:
+						tls: preferred
+						charset: utf8mb4
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-mysql-instance": mysql.Config{
 					Name:     "my-mysql-instance",
-					Type:     mysql.SourceType,
+					Kind:     mysql.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -120,11 +120,15 @@ func TestParseFromYamlCloudSQLMySQL(t *testing.T) {
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if diff := cmp.Diff(tc.want, got, cmpopts.EquateEmpty()); diff != "" {
+			if diff := cmp.Diff(tc.want, got.Sources, cmpopts.EquateEmpty()); diff != "" {
 				t.Fatalf("mismatch (-want +got):\n%s", diff)
 			}
 		})
@@ -141,51 +145,55 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"mysql\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | name: my-mysql-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unknown field \"foo\"",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"mysql\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
+			err: "Field validation for 'Host' failed",
 		},
 		{
 			desc: "invalid query params type",
 			in: `
-			kind: sources
-			name: my-mysql-instance
-			type: mysql
-			host: 0.0.0.0
-			port: 3306
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryParams: not-a-map
+			sources:
+				my-mysql-instance:
+					kind: mysql
+					host: 0.0.0.0
+					port: 3306
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryParams: not-a-map
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-mysql-instance\" as \"mysql\": [6:14] string was used where mapping is expected\n   3 | name: my-mysql-instance\n   4 | password: my_pass\n   5 | port: 3306\n>  6 | queryParams: not-a-map\n                    ^\n   7 | type: mysql\n   8 | user: my_user",
+			err: "string was used where mapping is expected",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}
@@ -203,7 +211,7 @@ func TestFailInitialization(t *testing.T) {
 
 	cfg := mysql.Config{
 		Name:         "instance",
-		Type:         "mysql",
+		Kind:         "mysql",
 		Host:         "localhost",
 		Port:         "3306",
 		Database:     "db",

internal/sources/neo4j/neo4j.go

@@ -29,7 +29,7 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "neo4j"
+const SourceKind string = "neo4j"
 
 var sourceClassifier *classifier.QueryClassifier = classifier.NewQueryClassifier()
 
@@ -37,8 +37,8 @@ var sourceClassifier *classifier.QueryClassifier = classifier.NewQueryClassifier
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -52,15 +52,15 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Uri      string `yaml:"uri" validate:"required"`
 	User     string `yaml:"user" validate:"required"`
 	Password string `yaml:"password" validate:"required"`
 	Database string `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -91,8 +91,8 @@ type Source struct {
 	Driver neo4j.DriverWithContext
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -182,7 +182,7 @@ func addPlanChildren(p neo4j.Plan) []map[string]any {
 
 func initNeo4jDriver(ctx context.Context, tracer trace.Tracer, uri, user, password, name string) (neo4j.DriverWithContext, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	auth := neo4j.BasicAuth(user, password, "")

internal/sources/neo4j/neo4j_test.go

@@ -15,12 +15,11 @@
 package neo4j_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/neo4j"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,18 +33,18 @@ func TestParseFromYamlNeo4j(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-neo4j-instance
-			type: neo4j
-			uri: neo4j+s://my-host:7687
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-neo4j-instance:
+					kind: neo4j
+					uri: neo4j+s://my-host:7687
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-neo4j-instance": neo4j.Config{
 					Name:     "my-neo4j-instance",
-					Type:     neo4j.SourceType,
+					Kind:     neo4j.SourceKind,
 					Uri:      "neo4j+s://my-host:7687",
 					Database: "my_db",
 					User:     "my_user",
@@ -56,12 +55,16 @@ func TestParseFromYamlNeo4j(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -77,33 +80,37 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-neo4j-instance
-			type: neo4j
-			uri: neo4j+s://my-host:7687
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-neo4j-instance:
+					kind: neo4j
+					uri: neo4j+s://my-host:7687
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-neo4j-instance\" as \"neo4j\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | name: my-neo4j-instance\n   4 | password: my_pass\n   5 | type: neo4j\n   6 | ",
+			err: "unable to parse source \"my-neo4j-instance\" as \"neo4j\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | kind: neo4j\n   4 | password: my_pass\n   5 | uri: neo4j+s://my-host:7687\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-neo4j-instance
-			type: neo4j
-			uri: neo4j+s://my-host:7687
-			database: my_db
-			user: my_user
+			sources:
+				my-neo4j-instance:
+					kind: neo4j
+					uri: neo4j+s://my-host:7687
+					database: my_db
+					user: my_user
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-neo4j-instance\" as \"neo4j\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
+			err: "unable to parse source \"my-neo4j-instance\" as \"neo4j\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/oceanbase/oceanbase.go

@@ -27,14 +27,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "oceanbase"
+const SourceKind string = "oceanbase"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -48,7 +48,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name         string `yaml:"name" validate:"required"`
-	Type         string `yaml:"type" validate:"required"`
+	Kind         string `yaml:"kind" validate:"required"`
 	Host         string `yaml:"host" validate:"required"`
 	Port         string `yaml:"port" validate:"required"`
 	User         string `yaml:"user" validate:"required"`
@@ -57,8 +57,8 @@ type Config struct {
 	QueryTimeout string `yaml:"queryTimeout"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -86,8 +86,8 @@ type Source struct {
 	Pool *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -153,7 +153,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 }
 
 func initOceanBaseConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname, queryTimeout string) (*sql.DB, error) {
-	_, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	_, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?parseTime=true", user, pass, host, port, dbname)

internal/sources/oceanbase/oceanbase_test.go

@@ -15,12 +15,11 @@
 package oceanbase_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/oceanbase"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -35,19 +34,19 @@ func TestParseFromYamlOceanBase(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-oceanbase-instance
-			type: oceanbase
-			host: 0.0.0.0
-			port: 2881
-			database: ob_db
-			user: ob_user
-			password: ob_pass
+			sources:
+				my-oceanbase-instance:
+					kind: oceanbase
+					host: 0.0.0.0
+					port: 2881
+					database: ob_db
+					user: ob_user
+					password: ob_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-oceanbase-instance": oceanbase.Config{
 					Name:     "my-oceanbase-instance",
-					Type:     oceanbase.SourceType,
+					Kind:     oceanbase.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "2881",
 					Database: "ob_db",
@@ -59,20 +58,20 @@ func TestParseFromYamlOceanBase(t *testing.T) {
 		{
 			desc: "with query timeout",
 			in: `
-			kind: sources
-			name: my-oceanbase-instance
-			type: oceanbase
-			host: 0.0.0.0
-			port: 2881
-			database: ob_db
-			user: ob_user
-			password: ob_pass
-			queryTimeout: 30s
+			sources:
+				my-oceanbase-instance:
+					kind: oceanbase
+					host: 0.0.0.0
+					port: 2881
+					database: ob_db
+					user: ob_user
+					password: ob_pass
+					queryTimeout: 30s
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-oceanbase-instance": oceanbase.Config{
 					Name:         "my-oceanbase-instance",
-					Type:         oceanbase.SourceType,
+					Kind:         oceanbase.SourceKind,
 					Host:         "0.0.0.0",
 					Port:         "2881",
 					Database:     "ob_db",
@@ -85,12 +84,16 @@ func TestParseFromYamlOceanBase(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -106,35 +109,39 @@ func TestFailParseFromYamlOceanBase(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-oceanbase-instance
-			type: oceanbase
-			host: 0.0.0.0
-			port: 2881
-			database: ob_db
-			user: ob_user
-			password: ob_pass
-			foo: bar
+			sources:
+				my-oceanbase-instance:
+					kind: oceanbase
+					host: 0.0.0.0
+					port: 2881
+					database: ob_db
+					user: ob_user
+					password: ob_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oceanbase-instance\" as \"oceanbase\": [2:1] unknown field \"foo\"\n   1 | database: ob_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | name: my-oceanbase-instance\n   5 | password: ob_pass\n   6 | ",
+			err: "unable to parse source \"my-oceanbase-instance\" as \"oceanbase\": [2:1] unknown field \"foo\"\n   1 | database: ob_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | kind: oceanbase\n   5 | password: ob_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-oceanbase-instance
-			type: oceanbase
-			port: 2881
-			database: ob_db
-			user: ob_user
-			password: ob_pass
+			sources:
+				my-oceanbase-instance:
+					kind: oceanbase
+					port: 2881
+					database: ob_db
+					user: ob_user
+					password: ob_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oceanbase-instance\" as \"oceanbase\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
+			err: "unable to parse source \"my-oceanbase-instance\" as \"oceanbase\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/oracle/oracle.go

@@ -18,14 +18,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "oracle"
+const SourceKind string = "oracle"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -45,7 +45,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name             string `yaml:"name" validate:"required"`
-	Type             string `yaml:"type" validate:"required"`
+	Kind             string `yaml:"kind" validate:"required"`
 	ConnectionString string `yaml:"connectionString,omitempty"`
 	TnsAlias         string `yaml:"tnsAlias,omitempty"`
 	TnsAdmin         string `yaml:"tnsAdmin,omitempty"`
@@ -95,8 +95,8 @@ func (c Config) validate() error {
 	return nil
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -124,8 +124,8 @@ type Source struct {
 	DB *sql.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -239,7 +239,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initOracleConnection(ctx context.Context, tracer trace.Tracer, config Config) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, config.Name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, config.Name)
 	defer span.End()
 
 	logger, err := util.LoggerFromContext(ctx)

internal/sources/oracle/oracle_test.go

@@ -3,13 +3,12 @@
 package oracle_test
 
 import (
-	"context"
 	"strings"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/oracle"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -23,18 +22,18 @@ func TestParseFromYamlOracle(t *testing.T) {
 		{
 			desc: "connection string and useOCI=true",
 			in: `
-			kind: sources
-			name: my-oracle-cs
-			type: oracle
-			connectionString: "my-host:1521/XEPDB1"
-			user: my_user
-			password: my_pass
-			useOCI: true
-			`,
-			want: map[string]sources.SourceConfig{
+            sources:
+                my-oracle-cs:
+                    kind: oracle
+                    connectionString: "my-host:1521/XEPDB1"
+                    user: my_user
+                    password: my_pass
+                    useOCI: true
+            `,
+			want: server.SourceConfigs{
 				"my-oracle-cs": oracle.Config{
 					Name:             "my-oracle-cs",
-					Type:             oracle.SourceType,
+					Kind:             oracle.SourceKind,
 					ConnectionString: "my-host:1521/XEPDB1",
 					User:             "my_user",
 					Password:         "my_pass",
@@ -45,19 +44,19 @@ func TestParseFromYamlOracle(t *testing.T) {
 		{
 			desc: "host/port/serviceName and default useOCI=false",
 			in: `
-			kind: sources
-			name: my-oracle-host
-			type: oracle
-			host: my-host
-			port: 1521
-			serviceName: ORCLPDB
-			user: my_user
-			password: my_pass
-			`,
-			want: map[string]sources.SourceConfig{
+            sources:
+                my-oracle-host:
+                    kind: oracle
+                    host: my-host
+                    port: 1521
+                    serviceName: ORCLPDB
+                    user: my_user
+                    password: my_pass
+            `,
+			want: server.SourceConfigs{
 				"my-oracle-host": oracle.Config{
 					Name:        "my-oracle-host",
-					Type:        oracle.SourceType,
+					Kind:        oracle.SourceKind,
 					Host:        "my-host",
 					Port:        1521,
 					ServiceName: "ORCLPDB",
@@ -70,19 +69,19 @@ func TestParseFromYamlOracle(t *testing.T) {
 		{
 			desc: "tnsAlias and TnsAdmin specified with explicit useOCI=true",
 			in: `
-			kind: sources
-			name: my-oracle-tns-oci
-			type: oracle
-			tnsAlias: FINANCE_DB
-			tnsAdmin: /opt/oracle/network/admin
-			user: my_user
-			password: my_pass
-			useOCI: true 
-			`,
-			want: map[string]sources.SourceConfig{
+            sources:
+                my-oracle-tns-oci:
+                    kind: oracle
+                    tnsAlias: FINANCE_DB
+                    tnsAdmin: /opt/oracle/network/admin
+                    user: my_user
+                    password: my_pass
+                    useOCI: true 
+            `,
+			want: server.SourceConfigs{
 				"my-oracle-tns-oci": oracle.Config{
 					Name:     "my-oracle-tns-oci",
-					Type:     oracle.SourceType,
+					Kind:     oracle.SourceKind,
 					TnsAlias: "FINANCE_DB",
 					TnsAdmin: "/opt/oracle/network/admin",
 					User:     "my_user",
@@ -94,18 +93,22 @@ func TestParseFromYamlOracle(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse:\nwant: %v\ngot:  %v\ndiff: %s", tc.want, got, cmp.Diff(tc.want, got))
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse:\nwant: %v\ngot:  %v\ndiff: %s", tc.want, got.Sources, cmp.Diff(tc.want, got.Sources))
 			}
 		})
 	}
 }
 
-func TestFailParseFromYaml(t *testing.T) {
+func TestFailParseFromYamlOracle(t *testing.T) {
 	tcs := []struct {
 		desc string
 		in   string
@@ -114,72 +117,76 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-oracle-instance
-			type: oracle
-			host: my-host
-			serviceName: ORCL
-			user: my_user
-			password: my_pass
-			extraField: value
+			sources:
+				my-oracle-instance:
+					kind: oracle
+					host: my-host
+					serviceName: ORCL
+					user: my_user
+					password: my_pass
+					extraField: value
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oracle-instance\" as \"oracle\": [1:1] unknown field \"extraField\"\n>  1 | extraField: value\n       ^\n   2 | host: my-host\n   3 | name: my-oracle-instance\n   4 | password: my_pass\n   5 | ",
+			err: "unable to parse source \"my-oracle-instance\" as \"oracle\": [1:1] unknown field \"extraField\"\n>  1 | extraField: value\n       ^\n   2 | host: my-host\n   3 | kind: oracle\n   4 | password: my_pass\n   5 | ",
 		},
 		{
 			desc: "missing required password field",
 			in: `
-			kind: sources
-			name: my-oracle-instance
-			type: oracle
-			host: my-host
-			serviceName: ORCL
-			user: my_user
-			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oracle-instance\" as \"oracle\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
+            sources:
+                my-oracle-instance:
+                    kind: oracle
+                    host: my-host
+                    serviceName: ORCL
+                    user: my_user
+            `,
+			err: "unable to parse source \"my-oracle-instance\" as \"oracle\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
 		},
 		{
 			desc: "missing connection method fields (validate fails)",
 			in: `
-			kind: sources
-			name: my-oracle-instance
-			type: oracle
-			user: my_user
-			password: my_pass
-			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oracle-instance\" as \"oracle\": invalid Oracle configuration: must provide one of: 'tns_alias', 'connection_string', or both 'host' and 'service_name'",
+            sources:
+                my-oracle-instance:
+                    kind: oracle
+                    user: my_user
+                    password: my_pass
+            `,
+			err: "unable to parse source \"my-oracle-instance\" as \"oracle\": invalid Oracle configuration: must provide one of: 'tns_alias', 'connection_string', or both 'host' and 'service_name'",
 		},
 		{
 			desc: "multiple connection methods provided (validate fails)",
 			in: `
-			kind: sources
-			name: my-oracle-instance
-			type: oracle
-			host: my-host
-			serviceName: ORCL
-			connectionString: "my-host:1521/XEPDB1"
-			user: my_user
-			password: my_pass
-			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oracle-instance\" as \"oracle\": invalid Oracle configuration: provide only one connection method: 'tns_alias', 'connection_string', or 'host'+'service_name'",
+            sources:
+                my-oracle-instance:
+                    kind: oracle
+                    host: my-host
+                    serviceName: ORCL
+                    connectionString: "my-host:1521/XEPDB1"
+                    user: my_user
+                    password: my_pass
+            `,
+			err: "unable to parse source \"my-oracle-instance\" as \"oracle\": invalid Oracle configuration: provide only one connection method: 'tns_alias', 'connection_string', or 'host'+'service_name'",
 		},
 		{
 			desc: "fail on tnsAdmin with useOCI=false",
 			in: `
-			kind: sources
-			name: my-oracle-fail
-			type: oracle
-			tnsAlias: FINANCE_DB
-			tnsAdmin: /opt/oracle/network/admin
-			user: my_user
-			password: my_pass
-			useOCI: false
+			sources:
+				my-oracle-fail:
+					kind: oracle
+					tnsAlias: FINANCE_DB
+					tnsAdmin: /opt/oracle/network/admin
+					user: my_user
+					password: my_pass
+					useOCI: false
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-oracle-fail\" as \"oracle\": invalid Oracle configuration: `tnsAdmin` can only be used when `UseOCI` is true, or use `walletLocation` instead",
+			err: "unable to parse source \"my-oracle-fail\" as \"oracle\": invalid Oracle configuration: `tnsAdmin` can only be used when `UseOCI` is true, or use `walletLocation` instead",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/postgres/postgres.go

@@ -28,14 +28,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "postgres"
+const SourceKind string = "postgres"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -49,7 +49,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name        string            `yaml:"name" validate:"required"`
-	Type        string            `yaml:"type" validate:"required"`
+	Kind        string            `yaml:"kind" validate:"required"`
 	Host        string            `yaml:"host" validate:"required"`
 	Port        string            `yaml:"port" validate:"required"`
 	User        string            `yaml:"user" validate:"required"`
@@ -58,8 +58,8 @@ type Config struct {
 	QueryParams map[string]string `yaml:"queryParams"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -87,8 +87,8 @@ type Source struct {
 	Pool *pgxpool.Pool
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -128,7 +128,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initPostgresConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname string, queryParams map[string]string) (*pgxpool.Pool, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 	userAgent, err := util.UserAgentFromContext(ctx)
 	if err != nil {

internal/sources/postgres/postgres_test.go

@@ -1,4 +1,4 @@
-// Copyright 2025 Google LLC
+// Copyright 2024 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,14 +15,13 @@
 package postgres_test
 
 import (
-	"context"
 	"sort"
 	"strings"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/postgres"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -36,19 +35,19 @@ func TestParseFromYamlPostgres(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: postgres
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-pg-instance:
+					kind: postgres
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": postgres.Config{
 					Name:     "my-pg-instance",
-					Type:     postgres.SourceType,
+					Kind:     postgres.SourceKind,
 					Host:     "my-host",
 					Port:     "my-port",
 					Database: "my_db",
@@ -60,22 +59,22 @@ func TestParseFromYamlPostgres(t *testing.T) {
 		{
 			desc: "example with query params",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: postgres
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryParams:
-				sslmode: verify-full
-				sslrootcert: /tmp/ca.crt
+			sources:
+				my-pg-instance:
+					kind: postgres
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryParams:
+						sslmode: verify-full
+						sslrootcert: /tmp/ca.crt
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-pg-instance": postgres.Config{
 					Name:     "my-pg-instance",
-					Type:     postgres.SourceType,
+					Kind:     postgres.SourceKind,
 					Host:     "my-host",
 					Port:     "my-port",
 					Database: "my_db",
@@ -91,12 +90,16 @@ func TestParseFromYamlPostgres(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -112,35 +115,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: postgres
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-pg-instance:
+					kind: postgres
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"postgres\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: my-host\n   4 | name: my-pg-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-pg-instance\" as \"postgres\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: my-host\n   4 | kind: postgres\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-pg-instance
-			type: postgres
-			host: my-host
-			port: my-port
-			database: my_db
-			user: my_user
+			sources:
+				my-pg-instance:
+					kind: postgres
+					host: my-host
+					port: my-port
+					database: my_db
+					user: my_user
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-pg-instance\" as \"postgres\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
+			err: "unable to parse source \"my-pg-instance\" as \"postgres\": Key: 'Config.Password' Error:Field validation for 'Password' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/redis/redis.go

@@ -24,14 +24,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "redis"
+const SourceKind string = "redis"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -45,7 +45,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name           string   `yaml:"name" validate:"required"`
-	Type           string   `yaml:"type" validate:"required"`
+	Kind           string   `yaml:"kind" validate:"required"`
 	Address        []string `yaml:"address" validate:"required"`
 	Username       string   `yaml:"username"`
 	Password       string   `yaml:"password"`
@@ -54,8 +54,8 @@ type Config struct {
 	ClusterEnabled bool     `yaml:"clusterEnabled"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // RedisClient is an interface for `redis.Client` and `redis.ClusterClient
@@ -141,8 +141,8 @@ type Source struct {
 	Client RedisClient
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/redis/redis_test.go

@@ -15,13 +15,12 @@
 package redis_test
 
 import (
-	"context"
 	"strings"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/redis"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -35,16 +34,16 @@ func TestParseFromYamlRedis(t *testing.T) {
 		{
 			desc: "default setting",
 			in: `
-			kind: sources
-			name: my-redis-instance
-			type: redis
-			address:
-			  - 127.0.0.1
+			sources:
+				my-redis-instance:
+					kind: redis
+					address:
+					  - 127.0.0.1
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-redis-instance": redis.Config{
 					Name:           "my-redis-instance",
-					Type:           redis.SourceType,
+					Kind:           redis.SourceKind,
 					Address:        []string{"127.0.0.1"},
 					ClusterEnabled: false,
 					UseGCPIAM:      false,
@@ -54,20 +53,20 @@ func TestParseFromYamlRedis(t *testing.T) {
 		{
 			desc: "advanced example",
 			in: `
-			kind: sources
-			name: my-redis-instance
-			type: redis
-			address:
-			  - 127.0.0.1
-			password: my-pass
-			database: 1
-			useGCPIAM: true
-			clusterEnabled: true
+			sources:
+				my-redis-instance:
+					kind: redis
+					address:
+					  - 127.0.0.1
+					password: my-pass
+					database: 1
+					useGCPIAM: true
+					clusterEnabled: true
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-redis-instance": redis.Config{
 					Name:           "my-redis-instance",
-					Type:           redis.SourceType,
+					Kind:           redis.SourceKind,
 					Address:        []string{"127.0.0.1"},
 					Password:       "my-pass",
 					Database:       1,
@@ -79,12 +78,16 @@ func TestParseFromYamlRedis(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -100,43 +103,48 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "invalid database",
 			in: `
-			kind: sources
-			name: my-redis-instance
-			type: redis
-			address:
-			- 127.0.0.1
-			password: my-pass
-			database: data
+			sources:
+				my-redis-instance:
+					kind: redis
+					project: my-project
+					address:
+					  - 127.0.0.1
+					password: my-pass
+					database: data
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-redis-instance\" as \"redis\": [3:11] cannot unmarshal string into Go struct field Config.Database of type int\n   1 | address:\n   2 | - 127.0.0.1\n>  3 | database: data\n                 ^\n   4 | name: my-redis-instance\n   5 | password: my-pass\n   6 | type: redis",
+			err: "cannot unmarshal string into Go struct field .Sources of type int",
 		},
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-redis-instance
-			type: redis
-			project: my-project
-			address:
-			- 127.0.0.1
-			password: my-pass
-			database: 1
+			sources:
+				my-redis-instance:
+					kind: redis
+					project: my-project
+					address:
+					  - 127.0.0.1
+					password: my-pass
+					database: 1
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-redis-instance\" as \"redis\": [6:1] unknown field \"project\"\n   3 | database: 1\n   4 | name: my-redis-instance\n   5 | password: my-pass\n>  6 | project: my-project\n       ^\n   7 | type: redis",
+			err: "unable to parse source \"my-redis-instance\" as \"redis\": [6:1] unknown field \"project\"",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-redis-instance
-			type: redis
+			sources:
+				my-redis-instance:
+					kind: redis
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-redis-instance\" as \"redis\": Key: 'Config.Address' Error:Field validation for 'Address' failed on the 'required' tag",
+			err: "unable to parse source \"my-redis-instance\" as \"redis\": Key: 'Config.Address' Error:Field validation for 'Address' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/serverlessspark/serverlessspark.go

@@ -33,14 +33,14 @@ import (
 	"google.golang.org/protobuf/encoding/protojson"
 )
 
-const SourceType string = "serverless-spark"
+const SourceKind string = "serverless-spark"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -54,13 +54,13 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string `yaml:"name" validate:"required"`
-	Type     string `yaml:"type" validate:"required"`
+	Kind     string `yaml:"kind" validate:"required"`
 	Project  string `yaml:"project" validate:"required"`
 	Location string `yaml:"location" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -94,8 +94,8 @@ type Source struct {
 	OpsClient *longrunning.OperationsClient
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {

internal/sources/serverlessspark/serverlessspark_test.go

@@ -15,12 +15,11 @@
 package serverlessspark_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/serverlessspark"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,16 +33,16 @@ func TestParseFromYamlServerlessSpark(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-				kind: sources
-				name: my-instance
-				type: serverless-spark
-				project: my-project
-				location: my-location
+				sources:
+					my-instance:
+						kind: serverless-spark
+						project: my-project
+						location: my-location
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-instance": serverlessspark.Config{
 					Name:     "my-instance",
-					Type:     serverlessspark.SourceType,
+					Kind:     serverlessspark.SourceKind,
 					Project:  "my-project",
 					Location: "my-location",
 				},
@@ -52,12 +51,16 @@ func TestParseFromYamlServerlessSpark(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -73,39 +76,43 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-				kind: sources
-				name: my-instance
-				type: serverless-spark
-				project: my-project
-				location: my-location
-				foo: bar
+				sources:
+					my-instance:
+						kind: serverless-spark
+						project: my-project
+						location: my-location
+						foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"serverless-spark\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | location: my-location\n   3 | name: my-instance\n   4 | project: my-project\n   5 | ",
+			err: "unable to parse source \"my-instance\" as \"serverless-spark\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | kind: serverless-spark\n   3 | location: my-location\n   4 | project: my-project",
 		},
 		{
 			desc: "missing required field project",
 			in: `
-				kind: sources
-				name: my-instance
-				type: serverless-spark
-				location: my-location
+				sources:
+					my-instance:
+						kind: serverless-spark
+						location: my-location
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"serverless-spark\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
+			err: "unable to parse source \"my-instance\" as \"serverless-spark\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
 		},
 		{
 			desc: "missing required field location",
 			in: `
-				kind: sources
-				name: my-instance
-				type: serverless-spark
-				project: my-project
+				sources:
+					my-instance:
+						kind: serverless-spark
+						project: my-project
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-instance\" as \"serverless-spark\": Key: 'Config.Location' Error:Field validation for 'Location' failed on the 'required' tag",
+			err: "unable to parse source \"my-instance\" as \"serverless-spark\": Key: 'Config.Location' Error:Field validation for 'Location' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/singlestore/singlestore.go

@@ -29,15 +29,15 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-// SourceType for SingleStore source
-const SourceType string = "singlestore"
+// SourceKind for SingleStore source
+const SourceKind string = "singlestore"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -52,7 +52,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 // Config holds the configuration parameters for connecting to a SingleStore database.
 type Config struct {
 	Name         string `yaml:"name" validate:"required"`
-	Type         string `yaml:"type" validate:"required"`
+	Kind         string `yaml:"kind" validate:"required"`
 	Host         string `yaml:"host" validate:"required"`
 	Port         string `yaml:"port" validate:"required"`
 	User         string `yaml:"user" validate:"required"`
@@ -61,9 +61,9 @@ type Config struct {
 	QueryTimeout string `yaml:"queryTimeout"`
 }
 
-// SourceConfigType returns the type of the source configuration.
-func (r Config) SourceConfigType() string {
-	return SourceType
+// SourceConfigKind returns the kind of the source configuration.
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 // Initialize sets up the SingleStore connection pool and returns a Source.
@@ -93,9 +93,9 @@ type Source struct {
 	Pool *sql.DB
 }
 
-// SourceType returns the type of the source configuration.
-func (s *Source) SourceType() string {
-	return SourceType
+// SourceKind returns the kind of the source configuration.
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -162,7 +162,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initSingleStoreConnectionPool(ctx context.Context, tracer trace.Tracer, name, host, port, user, pass, dbname, queryTimeout string) (*sql.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Configure the driver to connect to the database

internal/sources/singlestore/singlestore_test.go

@@ -1,3 +1,5 @@
+package singlestore_test
+
 // Copyright 2025 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -12,15 +14,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package singlestore_test
-
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/singlestore"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYaml(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-			kind: sources
-			name: my-s2-instance
-			type: singlestore
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-s2-instance:
+					kind: singlestore
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-s2-instance": singlestore.Config{
 					Name:     "my-s2-instance",
-					Type:     singlestore.SourceType,
+					Kind:     singlestore.SourceKind,
 					Host:     "0.0.0.0",
 					Port:     "my-port",
 					Database: "my_db",
@@ -58,20 +57,20 @@ func TestParseFromYaml(t *testing.T) {
 		{
 			desc: "with query timeout",
 			in: `
-			kind: sources
-			name: my-s2-instance
-			type: singlestore
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			queryTimeout: 45s
+			sources:
+				my-s2-instance:
+					kind: singlestore
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					queryTimeout: 45s
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-s2-instance": singlestore.Config{
 					Name:         "my-s2-instance",
-					Type:         singlestore.SourceType,
+					Kind:         singlestore.SourceKind,
 					Host:         "0.0.0.0",
 					Port:         "my-port",
 					Database:     "my_db",
@@ -84,12 +83,16 @@ func TestParseFromYaml(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -105,35 +108,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-			kind: sources
-			name: my-s2-instance
-			type: singlestore
-			host: 0.0.0.0
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
-			foo: bar
+			sources:
+				my-s2-instance:
+					kind: singlestore
+					host: 0.0.0.0
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
+					foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-s2-instance\" as \"singlestore\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | name: my-s2-instance\n   5 | password: my_pass\n   6 | ",
+			err: "unable to parse source \"my-s2-instance\" as \"singlestore\": [2:1] unknown field \"foo\"\n   1 | database: my_db\n>  2 | foo: bar\n       ^\n   3 | host: 0.0.0.0\n   4 | kind: singlestore\n   5 | password: my_pass\n   6 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-			kind: sources
-			name: my-s2-instance
-			type: singlestore
-			port: my-port
-			database: my_db
-			user: my_user
-			password: my_pass
+			sources:
+				my-s2-instance:
+					kind: singlestore
+					port: my-port
+					database: my_db
+					user: my_user
+					password: my_pass
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-s2-instance\" as \"singlestore\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
+			err: "unable to parse source \"my-s2-instance\" as \"singlestore\": Key: 'Config.Host' Error:Field validation for 'Host' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/snowflake/snowflake.go

@@ -25,14 +25,14 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
-const SourceType string = "snowflake"
+const SourceKind string = "snowflake"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -46,7 +46,7 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name      string `yaml:"name" validate:"required"`
-	Type      string `yaml:"type" validate:"required"`
+	Kind      string `yaml:"kind" validate:"required"`
 	Account   string `yaml:"account" validate:"required"`
 	User      string `yaml:"user" validate:"required"`
 	Password  string `yaml:"password" validate:"required"`
@@ -56,8 +56,8 @@ type Config struct {
 	Role      string `yaml:"role"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -85,8 +85,8 @@ type Source struct {
 	DB *sqlx.DB
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -137,7 +137,7 @@ func (s *Source) RunSQL(ctx context.Context, statement string, params []any) (an
 
 func initSnowflakeConnection(ctx context.Context, tracer trace.Tracer, name, account, user, password, database, schema, warehouse, role string) (*sqlx.DB, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Set defaults for optional parameters

internal/sources/snowflake/snowflake_test.go

@@ -15,12 +15,11 @@
 package snowflake_test
 
 import (
-	"context"
 	"testing"
 
+	yaml "github.com/goccy/go-yaml"
 	"github.com/google/go-cmp/cmp"
 	"github.com/googleapis/genai-toolbox/internal/server"
-	"github.com/googleapis/genai-toolbox/internal/sources"
 	"github.com/googleapis/genai-toolbox/internal/sources/snowflake"
 	"github.com/googleapis/genai-toolbox/internal/testutils"
 )
@@ -34,19 +33,19 @@ func TestParseFromYamlSnowflake(t *testing.T) {
 		{
 			desc: "basic example",
 			in: `
-				kind: sources
-				name: my-snowflake-instance
-				type: snowflake
-				account: my-account
-				user: my_user
-				password: my_pass
-				database: my_db
-				schema: my_schema
+				sources:
+					my-snowflake-instance:
+						kind: snowflake
+						account: my-account
+						user: my_user
+						password: my_pass
+						database: my_db
+						schema: my_schema
 			`,
-			want: map[string]sources.SourceConfig{
+			want: server.SourceConfigs{
 				"my-snowflake-instance": snowflake.Config{
 					Name:      "my-snowflake-instance",
-					Type:      snowflake.SourceType,
+					Kind:      snowflake.SourceKind,
 					Account:   "my-account",
 					User:      "my_user",
 					Password:  "my_pass",
@@ -60,12 +59,16 @@ func TestParseFromYamlSnowflake(t *testing.T) {
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err != nil {
 				t.Fatalf("unable to unmarshal: %s", err)
 			}
-			if !cmp.Equal(tc.want, got) {
-				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got)
+			if !cmp.Equal(tc.want, got.Sources) {
+				t.Fatalf("incorrect parse: want %v, got %v", tc.want, got.Sources)
 			}
 		})
 	}
@@ -81,35 +84,39 @@ func TestFailParseFromYaml(t *testing.T) {
 		{
 			desc: "extra field",
 			in: `
-				kind: sources
-				name: my-snowflake-instance
-				type: snowflake
-				account: my-account
-				user: my_user
-				password: my_pass
-				database: my_db
-				schema: my_schema
-				foo: bar
+				sources:
+					my-snowflake-instance:
+						kind: snowflake
+						account: my-account
+						user: my_user
+						password: my_pass
+						database: my_db
+						schema: my_schema
+						foo: bar
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-snowflake-instance\" as \"snowflake\": [3:1] unknown field \"foo\"\n   1 | account: my-account\n   2 | database: my_db\n>  3 | foo: bar\n       ^\n   4 | name: my-snowflake-instance\n   5 | password: my_pass\n   6 | schema: my_schema\n   7 | ",
+			err: "unable to parse source \"my-snowflake-instance\" as \"snowflake\": [3:1] unknown field \"foo\"\n   1 | account: my-account\n   2 | database: my_db\n>  3 | foo: bar\n       ^\n   4 | kind: snowflake\n   5 | password: my_pass\n   6 | schema: my_schema\n   7 | ",
 		},
 		{
 			desc: "missing required field",
 			in: `
-				kind: sources
-				name: my-snowflake-instance
-				type: snowflake
-				account: my-account
-				user: my_user
-				password: my_pass
-				database: my_db
+				sources:
+					my-snowflake-instance:
+						kind: snowflake
+						account: my-account
+						user: my_user
+						password: my_pass
+						database: my_db
 			`,
-			err: "error unmarshaling sources: unable to parse source \"my-snowflake-instance\" as \"snowflake\": Key: 'Config.Schema' Error:Field validation for 'Schema' failed on the 'required' tag",
+			err: "unable to parse source \"my-snowflake-instance\" as \"snowflake\": Key: 'Config.Schema' Error:Field validation for 'Schema' failed on the 'required' tag",
 		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.desc, func(t *testing.T) {
-			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
+			got := struct {
+				Sources server.SourceConfigs `yaml:"sources"`
+			}{}
+			// Parse contents
+			err := yaml.Unmarshal(testutils.FormatYaml(tc.in), &got)
 			if err == nil {
 				t.Fatalf("expect parsing to fail")
 			}

internal/sources/sources.go

@@ -29,48 +29,48 @@ type SourceConfigFactory func(ctx context.Context, name string, decoder *yaml.De
 
 var sourceRegistry = make(map[string]SourceConfigFactory)
 
-// Register registers a new source type with its factory.
-// It returns false if the type is already registered.
-func Register(sourceType string, factory SourceConfigFactory) bool {
-	if _, exists := sourceRegistry[sourceType]; exists {
-		// Source with this type already exists, do not overwrite.
+// Register registers a new source kind with its factory.
+// It returns false if the kind is already registered.
+func Register(kind string, factory SourceConfigFactory) bool {
+	if _, exists := sourceRegistry[kind]; exists {
+		// Source with this kind already exists, do not overwrite.
 		return false
 	}
-	sourceRegistry[sourceType] = factory
+	sourceRegistry[kind] = factory
 	return true
 }
 
-// DecodeConfig decodes a source configuration using the registered factory for the given type.
-func DecodeConfig(ctx context.Context, sourceType string, name string, decoder *yaml.Decoder) (SourceConfig, error) {
-	factory, found := sourceRegistry[sourceType]
+// DecodeConfig decodes a source configuration using the registered factory for the given kind.
+func DecodeConfig(ctx context.Context, kind string, name string, decoder *yaml.Decoder) (SourceConfig, error) {
+	factory, found := sourceRegistry[kind]
 	if !found {
-		return nil, fmt.Errorf("unknown source type: %q", sourceType)
+		return nil, fmt.Errorf("unknown source kind: %q", kind)
 	}
 	sourceConfig, err := factory(ctx, name, decoder)
 	if err != nil {
-		return nil, fmt.Errorf("unable to parse source %q as %q: %w", name, sourceType, err)
+		return nil, fmt.Errorf("unable to parse source %q as %q: %w", name, kind, err)
 	}
 	return sourceConfig, err
 }
 
 // SourceConfig is the interface for configuring a source.
 type SourceConfig interface {
-	SourceConfigType() string
+	SourceConfigKind() string
 	Initialize(ctx context.Context, tracer trace.Tracer) (Source, error)
 }
 
 // Source is the interface for the source itself.
 type Source interface {
-	SourceType() string
+	SourceKind() string
 	ToConfig() SourceConfig
 }
 
 // InitConnectionSpan adds a span for database pool connection initialization
-func InitConnectionSpan(ctx context.Context, tracer trace.Tracer, sourceType, sourceName string) (context.Context, trace.Span) {
+func InitConnectionSpan(ctx context.Context, tracer trace.Tracer, sourceKind, sourceName string) (context.Context, trace.Span) {
 	ctx, span := tracer.Start(
 		ctx,
 		"toolbox/server/source/connect",
-		trace.WithAttributes(attribute.String("source_type", sourceType)),
+		trace.WithAttributes(attribute.String("source_kind", sourceKind)),
 		trace.WithAttributes(attribute.String("source_name", sourceName)),
 	)
 	return ctx, span

internal/sources/spanner/spanner.go

@@ -28,14 +28,14 @@ import (
 	"google.golang.org/api/iterator"
 )
 
-const SourceType string = "spanner"
+const SourceKind string = "spanner"
 
 // validate interface
 var _ sources.SourceConfig = Config{}
 
 func init() {
-	if !sources.Register(SourceType, newConfig) {
-		panic(fmt.Sprintf("source type %q already registered", SourceType))
+	if !sources.Register(SourceKind, newConfig) {
+		panic(fmt.Sprintf("source kind %q already registered", SourceKind))
 	}
 }
 
@@ -49,15 +49,15 @@ func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (sources
 
 type Config struct {
 	Name     string          `yaml:"name" validate:"required"`
-	Type     string          `yaml:"type" validate:"required"`
+	Kind     string          `yaml:"kind" validate:"required"`
 	Project  string          `yaml:"project" validate:"required"`
 	Instance string          `yaml:"instance" validate:"required"`
 	Dialect  sources.Dialect `yaml:"dialect" validate:"required"`
 	Database string          `yaml:"database" validate:"required"`
 }
 
-func (r Config) SourceConfigType() string {
-	return SourceType
+func (r Config) SourceConfigKind() string {
+	return SourceKind
 }
 
 func (r Config) Initialize(ctx context.Context, tracer trace.Tracer) (sources.Source, error) {
@@ -80,8 +80,8 @@ type Source struct {
 	Client *spanner.Client
 }
 
-func (s *Source) SourceType() string {
-	return SourceType
+func (s *Source) SourceKind() string {
+	return SourceKind
 }
 
 func (s *Source) ToConfig() sources.SourceConfig {
@@ -171,7 +171,7 @@ func (s *Source) RunSQL(ctx context.Context, readOnly bool, statement string, pa
 
 func initSpannerClient(ctx context.Context, tracer trace.Tracer, name, project, instance, dbname string) (*spanner.Client, error) {
 	//nolint:all // Reassigned ctx
-	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceType, name)
+	ctx, span := sources.InitConnectionSpan(ctx, tracer, SourceKind, name)
 	defer span.End()
 
 	// Configure the connection to the database