chore: Update toolbox-adk dependency to pick the latest version

CONTRIBUTING.md

@@ -59,13 +59,6 @@ You can manually trigger the bot by commenting on your Pull Request:
 *   `/gemini summary`: Posts a summary of the changes in the pull request.
 *   `/gemini help`: Overview of the available commands
 
-## Guidelines for Pull Requests
-
-1. Please keep your PR small for more thorough review and easier updates. In case of regression, it also allows us to roll back a single feature instead of multiple ones.
-1. For non-trivial changes, consider opening an issue and discussing it with the code owners first.
-1. Provide a good PR description as a record of what change is being made and why it was made. Link to a GitHub issue if it exists.
-1. Make sure your code is thoroughly tested with unit tests and integration tests. Remember to clean up the test instances properly in your code to avoid memory leaks.
-
 ## Adding a New Database Source or Tool
 
 Please create an
@@ -92,11 +85,11 @@ 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 +97,7 @@ 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`.
 
@@ -117,8 +110,6 @@ implementation](https://github.com/googleapis/genai-toolbox/blob/main/internal/s
 We recommend looking at an [example tool
 implementation](https://github.com/googleapis/genai-toolbox/tree/main/internal/tools/postgres/postgressql).
 
-Remember to keep your PRs small. For example, if you are contributing a new Source, only include one or two core Tools within the same PR, the rest of the Tools can come in subsequent PRs. 
-
 * **Create a new directory** under `internal/tools` for your tool type (e.g., `internal/tools/newdb/newdbtool`).
 * **Define a configuration struct** for your tool in a file named `newdbtool.go`.
 Create a `Config` struct and a `Tool` struct to store necessary parameters for
@@ -126,7 +117,7 @@ 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
@@ -172,8 +163,6 @@ tools.
             parameters][temp-param-doc]. Only run this test if template
             parameters apply to your tool.
 
-* **Add additional tests** for the tools that are not covered by the predefined tests. Every tool must be tested!
-
 * **Add the new database to the integration test workflow** in
   [integration.cloudbuild.yaml](.ci/integration.cloudbuild.yaml).
 
@@ -243,7 +232,7 @@ 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
@@ -255,4 +244,4 @@ resources.
 * **PR Description:** PR description should **always** be included. It should
   include a concise description of the changes, it's impact, along with a
   summary of the solution. If the PR is related to a specific issue, the issue
-  number should be mentioned in the PR description (e.g. `Fixes #1`).
+  number should be mentioned in the PR description (e.g. `Fixes #1`).

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"
@@ -93,7 +92,6 @@ import (
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudhealthcare/cloudhealthcaresearchdicomstudies"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudmonitoring"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlcloneinstance"
-	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlcreatebackup"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlcreatedatabase"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlcreateusers"
 	_ "github.com/googleapis/genai-toolbox/internal/tools/cloudsql/cloudsqlgetinstances"
@@ -395,6 +393,7 @@ 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 +424,6 @@ 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 +434,8 @@ 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 +467,18 @@ 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 +954,20 @@ 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"},
 				},
 			},
 		},
@@ -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"},
 				},
 			},
 		},
@@ -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"},
 				},
 			},
 		},

docs/en/getting-started/colab_quickstart.ipynb

@@ -509,7 +509,7 @@
       },
       "outputs": [],
       "source": [
-        "! pip install toolbox-core --quiet\n",
+        "! pip install toolbox-adk --quiet\n",
         "! pip install google-adk --quiet"
       ]
     },
@@ -525,14 +525,18 @@
         "from google.adk.runners import Runner\n",
         "from google.adk.sessions import InMemorySessionService\n",
         "from google.adk.artifacts.in_memory_artifact_service import InMemoryArtifactService\n",
+        "from google.adk.tools.toolbox_toolset import ToolboxToolset\n",
         "from google.genai import types\n",
-        "from toolbox_core import ToolboxSyncClient\n",
         "\n",
         "import os\n",
         "# TODO(developer): replace this with your Google API key\n",
         "os.environ['GOOGLE_API_KEY'] = \"<GOOGLE_API_KEY>\"\n",
         "\n",
-        "toolbox_client = ToolboxSyncClient(\"http://127.0.0.1:5000\")\n",
+        "# Configure toolset\n",
+        "toolset = ToolboxToolset(\n",
+        "    server_url=\"http://127.0.0.1:5000\",\n",
+        "    toolset_name=\"my-toolset\"\n",
+        ")\n",
         "\n",
         "prompt = \"\"\"\n",
         "  You're a helpful hotel assistant. You handle hotel searching, booking and\n",
@@ -549,7 +553,7 @@
         "    name='hotel_agent',\n",
         "    description='A helpful AI assistant.',\n",
         "    instruction=prompt,\n",
-        "    tools=toolbox_client.load_toolset(\"my-toolset\"),\n",
+        "    tools=[toolset],\n",
         ")\n",
         "\n",
         "session_service = InMemorySessionService()\n",

docs/en/getting-started/local_quickstart.md

@@ -52,7 +52,7 @@ runtime](https://research.google.com/colaboratory/local-runtimes.html).
     {{< tabpane persist=header >}}
 {{< tab header="ADK" lang="bash" >}}
 
-pip install toolbox-core
+pip install toolbox-adk
 {{< /tab >}}
 {{< tab header="Langchain" lang="bash" >}}
 

docs/en/getting-started/quickstart/python/adk/quickstart.py

@@ -1,15 +1,17 @@
 from google.adk import Agent
 from google.adk.apps import App
-from toolbox_core import ToolboxSyncClient
+from google.adk.tools.toolbox_toolset import ToolboxToolset
 
 # TODO(developer): update the TOOLBOX_URL to your toolbox endpoint
-client = ToolboxSyncClient("http://127.0.0.1:5000")
+toolset = ToolboxToolset(
+    server_url="http://127.0.0.1:5000",
+)
 
 root_agent = Agent(
     name='root_agent',
     model='gemini-2.5-flash',
     instruction="You are a helpful AI assistant designed to provide accurate and useful information.",
-    tools=client.load_toolset(),
+    tools=[toolset],
 )
 
 app = App(root_agent=root_agent, name="my_agent")

docs/en/getting-started/quickstart/python/adk/requirements.txt

@@ -1,3 +1,3 @@
 google-adk==1.21.0
-toolbox-core==0.5.4
+toolbox-adk>=0.1.0
 pytest==9.0.2

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

@@ -48,7 +48,6 @@ instance, database and users:
     * `roles/cloudsql.editor`: Provides permissions to manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     * `roles/cloudsql.admin`: Provides full control over all resources.
         * All `editor` and `viewer` tools
         * `create_instance`
@@ -300,7 +299,6 @@ instances and interacting with your database:
 * **create_user**: Creates a new user in a Cloud SQL instance.
 * **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.
 
 {{< 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

@@ -48,7 +48,6 @@ database and users:
     * `roles/cloudsql.editor`: Provides permissions to manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     * `roles/cloudsql.admin`: Provides full control over all resources.
         * All `editor` and `viewer` tools
         * `create_instance`
@@ -300,7 +299,6 @@ instances and interacting with your database:
 * **create_user**: Creates a new user in a Cloud SQL instance.
 * **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.
 
 {{< 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

@@ -48,7 +48,6 @@ instance, database and users:
     * `roles/cloudsql.editor`: Provides permissions to manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     * `roles/cloudsql.admin`: Provides full control over all resources.
         * All `editor` and `viewer` tools
         * `create_instance`
@@ -300,7 +299,6 @@ instances and interacting with your database:
 * **create_user**: Creates a new user in a Cloud SQL instance.
 * **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.
 
 {{< notice note >}}
 Prebuilt tools are pre-1.0, so expect some tool changes between versions. LLMs

docs/en/how-to/deploy_adk_agent.md

@@ -49,7 +49,7 @@ with the necessary configuration for deployment to Vertex AI Agent Engine.
 4.  Add `toolbox-core` as a dependency to the new project:
 
     ```bash
-    uv add toolbox-core
+    uv add toolbox-adk
     ```
 
 ## Step 3: Configure Google Cloud Authentication
@@ -95,22 +95,23 @@ authentication token.
     ```python
     from google.adk import Agent
     from google.adk.apps import App
-    from toolbox_core import ToolboxSyncClient, auth_methods
+    from google.adk.tools.toolbox_toolset import ToolboxToolset
+    from toolbox_adk import CredentialStrategy
 
     # TODO(developer): Replace with your Toolbox Cloud Run Service URL
     TOOLBOX_URL = "https://your-toolbox-service-xyz.a.run.app"
 
-    # Initialize the client with the Cloud Run URL and Auth headers
-    client = ToolboxSyncClient(
-        TOOLBOX_URL, 
-        client_headers={"Authorization": auth_methods.get_google_id_token(TOOLBOX_URL)}
+    # Initialize the toolset with Workload Identity (generates ID token for the URL)
+    toolset = ToolboxToolset(
+        server_url=TOOLBOX_URL,
+        credentials=CredentialStrategy.workload_identity(target_audience=TOOLBOX_URL)
     )
 
     root_agent = Agent(
         name='root_agent',
         model='gemini-2.5-flash',
         instruction="You are a helpful AI assistant designed to provide accurate and useful information.",
-        tools=client.load_toolset(),
+        tools=[toolset],
     )
 
     app = App(root_agent=root_agent, name="my_agent")

docs/en/reference/prebuilt-tools.md

@@ -187,7 +187,6 @@ See [Usage Examples](../reference/cli.md#examples).
         manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     *   **Cloud SQL Admin** (`roles/cloudsql.admin`): Provides full control over
         all resources.
         * All `editor` and `viewer` tools
@@ -204,7 +203,6 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `create_user`: Creates a new user in a Cloud SQL instance.
     *   `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.
 
 ## Cloud SQL for PostgreSQL
 
@@ -277,7 +275,6 @@ See [Usage Examples](../reference/cli.md#examples).
         manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     *   **Cloud SQL Admin** (`roles/cloudsql.admin`): Provides full control over
         all resources.
         * All `editor` and `viewer` tools
@@ -293,7 +290,6 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `create_user`: Creates a new user in a Cloud SQL instance.
     *   `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.
 
 ## Cloud SQL for SQL Server
 
@@ -340,7 +336,6 @@ See [Usage Examples](../reference/cli.md#examples).
         manage existing resources.
         * All `viewer` tools
         * `create_database`
-        * `create_backup`
     *   **Cloud SQL Admin** (`roles/cloudsql.admin`): Provides full control over
         all resources.
         * All `editor` and `viewer` tools
@@ -356,7 +351,6 @@ See [Usage Examples](../reference/cli.md#examples).
     *   `create_user`: Creates a new user in a Cloud SQL instance.
     *   `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.
 
 ## Dataplex
 

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

@@ -1,45 +0,0 @@
----
-title: cloud-sql-create-backup
-type: docs
-weight: 10
-description: "Creates a backup on a Cloud SQL instance."
----
-
-The `cloud-sql-create-backup` tool creates an on-demand 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 creation (current state)
-
-```yaml
-tools:
-  backup-creation-basic:
-    kind: cloud-sql-create-backup
-    source: cloud-sql-admin-source
-    description: "Creates a backup on the given Cloud SQL instance."
-```
-## Reference
-### Tool Configuration
-| **field**      | **type** | **required** | **description**                                               |
-| -------------- | :------: | :----------: | ------------------------------------------------------------- |
-| kind           | string   | true         | Must be "cloud-sql-create-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**                                                                 |
-| -------------------------- | :------: | :----------: | ------------------------------------------------------------------------------- |
-| project                    | string   | true         | The project ID.                                                                 |
-| instance                   | string   | true         | The name of the instance to take a backup on. Does not include the project ID.  |
-| location                   | string   | false        | (Optional) Location of the backup run.                                          |
-| backup_description         | string   | false        | (Optional) The description of this backup run.                                  |
-
-## See Also
-- [Cloud SQL Admin API documentation](https://cloud.google.com/sql/docs/mysql/admin-api)
-- [Toolbox Cloud SQL tools documentation](../cloudsql)
-- [Cloud SQL Backup API documentation](https://cloud.google.com/sql/docs/mysql/backup-recovery/backups)

docs/en/samples/bigquery/local_quickstart.md

@@ -365,7 +365,7 @@ pip install llama-index-llms-google-genai
 
 {{< /tab >}}
 {{< tab header="ADK" lang="bash" >}}
-pip install toolbox-core
+pip install toolbox-adk
 {{< /tab >}}
 {{< /tabpane >}}
 
@@ -607,8 +607,8 @@ from google.adk.agents import Agent
 from google.adk.runners import Runner
 from google.adk.sessions import InMemorySessionService
 from google.adk.artifacts.in_memory_artifact_service import InMemoryArtifactService
+from google.adk.tools.toolbox_toolset import ToolboxToolset
 from google.genai import types # For constructing message content
-from toolbox_core import ToolboxSyncClient
 
 import os
 os.environ['GOOGLE_GENAI_USE_VERTEXAI'] = 'True'
@@ -623,48 +623,47 @@ os.environ['GOOGLE_CLOUD_LOCATION'] = 'us-central1'
 
 # --- Load Tools from Toolbox ---
 
-# TODO(developer): Ensure the Toolbox server is running at <http://127.0.0.1:5000>
+# TODO(developer): Ensure the Toolbox server is running at http://127.0.0.1:5000
+toolset = ToolboxToolset(server_url="http://127.0.0.1:5000")
 
-with ToolboxSyncClient("<http://127.0.0.1:5000>") as toolbox_client:
-    # TODO(developer): Replace "my-toolset" with the actual ID of your toolset as configured in your MCP Toolbox server.
-    agent_toolset = toolbox_client.load_toolset("my-toolset")
+# --- Define the Agent's Prompt ---
+prompt = """
+  You're a helpful hotel assistant. You handle hotel searching, booking and
+  cancellations. When the user searches for a hotel, mention it's name, id,
+  location and price tier. Always mention hotel ids while performing any
+  searches. This is very important for any operations. For any bookings or
+  cancellations, please provide the appropriate confirmation. Be sure to
+  update checkin or checkout dates if mentioned by the user.
+  Don't ask for confirmations from the user.
+"""
 
-    # --- Define the Agent's Prompt ---
-    prompt = """
-      You're a helpful hotel assistant. You handle hotel searching, booking and
-      cancellations. When the user searches for a hotel, mention it's name, id,
-      location and price tier. Always mention hotel ids while performing any
-      searches. This is very important for any operations. For any bookings or
-      cancellations, please provide the appropriate confirmation. Be sure to
-      update checkin or checkout dates if mentioned by the user.
-      Don't ask for confirmations from the user.
-    """
+# --- Configure the Agent ---
 
-    # --- Configure the Agent ---
+root_agent = Agent(
+    model='gemini-2.0-flash-001',
+    name='hotel_agent',
+    description='A helpful AI assistant that can search and book hotels.',
+    instruction=prompt,
+    tools=[toolset], # Pass the loaded toolset
+)
 
-    root_agent = Agent(
-        model='gemini-2.0-flash-001',
-        name='hotel_agent',
-        description='A helpful AI assistant that can search and book hotels.',
-        instruction=prompt,
-        tools=agent_toolset, # Pass the loaded toolset
-    )
+# --- Initialize Services for Running the Agent ---
+session_service = InMemorySessionService()
+artifacts_service = InMemoryArtifactService()
 
-    # --- Initialize Services for Running the Agent ---
-    session_service = InMemorySessionService()
-    artifacts_service = InMemoryArtifactService()
+runner = Runner(
+    app_name='hotel_agent',
+    agent=root_agent,
+    artifact_service=artifacts_service,
+    session_service=session_service,
+)
+
+async def main():
     # Create a new session for the interaction.
-    session = session_service.create_session(
+    session = await session_service.create_session(
         state={}, app_name='hotel_agent', user_id='123'
     )
 
-    runner = Runner(
-        app_name='hotel_agent',
-        agent=root_agent,
-        artifact_service=artifacts_service,
-        session_service=session_service,
-    )
-
     # --- Define Queries and Run the Agent ---
     queries = [
         "Find hotels in Basel with Basel in it's name.",
@@ -687,6 +686,10 @@ with ToolboxSyncClient("<http://127.0.0.1:5000>") as toolbox_client:
 
         for text in responses:
           print(text)
+
+import asyncio
+if __name__ == "__main__":
+    asyncio.run(main())
 {{< /tab >}}
 {{< /tabpane >}}
 

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

@@ -43,9 +43,6 @@ tools:
   clone_instance:
     kind: cloud-sql-clone-instance
     source: cloud-sql-admin-source
-  create_backup:
-    kind: cloud-sql-create-backup
-    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_mssql_admin_tools:
@@ -57,4 +54,3 @@ toolsets:
     - create_user
     - wait_for_operation
     - clone_instance
-    - create_backup

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

@@ -43,9 +43,6 @@ tools:
   clone_instance:
     kind: cloud-sql-clone-instance
     source: cloud-sql-admin-source
-  create_backup:
-    kind: cloud-sql-create-backup
-    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_mysql_admin_tools:
@@ -57,4 +54,3 @@ toolsets:
     - create_user
     - wait_for_operation
     - clone_instance
-    - create_backup

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

@@ -46,9 +46,6 @@ tools:
   postgres_upgrade_precheck:
     kind: postgres-upgrade-precheck
     source: cloud-sql-admin-source
-  create_backup:
-    kind: cloud-sql-create-backup
-    source: cloud-sql-admin-source
 
 toolsets:
   cloud_sql_postgres_admin_tools:
@@ -61,4 +58,3 @@ toolsets:
     - wait_for_operation
     - postgres_upgrade_precheck
     - clone_instance
-    - create_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 +14,8 @@
 package server
 
 import (
-	"bytes"
 	"context"
 	"fmt"
-	"io"
 	"strings"
 
 	yaml "github.com/goccy/go-yaml"
@@ -126,201 +124,272 @@ 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 {
+		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
 }

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()

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",
 			},
 		},
 	}

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

@@ -34,7 +34,7 @@ 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/([^/]+)`)
 
@@ -42,8 +42,8 @@ var targetLinkRegex = regexp.MustCompile(`/projects/([^/]+)/instances/([^/]+)/da
 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 +57,13 @@ 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 +110,8 @@ 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 {
@@ -352,28 +352,6 @@ func (s *Source) GetWaitForOperations(ctx context.Context, service *sqladmin.Ser
 	return nil, nil
 }
 
-func (s *Source) InsertBackupRun(ctx context.Context, project, instance, location, backupDescription, accessToken string) (any, error) {
-	backupRun := &sqladmin.BackupRun{}
-	if location != "" {
-		backupRun.Location = location
-	}
-	if backupDescription != "" {
-		backupRun.Description = backupDescription
-	}
-
-	service, err := s.GetService(ctx, string(accessToken))
-	if err != nil {
-		return nil, err
-	}
-
-	resp, err := service.BackupRuns.Insert(project, instance, backupRun).Do()
-	if err != nil {
-		return nil, fmt.Errorf("error creating 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