update agentError constructor

## Description

> Should include a concise description of the changes (bug or feature),
it's
> impact, along with a summary of the solution

## PR Checklist

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

- [ ] Make sure you reviewed

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

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

🛠️ Fixes #<issue_number_goes_here>

docs/en/reference/prebuilt-tools.md

@@ -414,10 +414,10 @@ See [Usage Examples](../reference/cli.md#examples).
         entries.
     *   **Dataplex Editor** (`roles/dataplex.editor`) to modify entries.
 *   **Tools:**
-    *   `dataplex_search_entries`: Searches for entries in Dataplex Catalog.
+    *   `search_entries`: Searches for entries in Dataplex Catalog.
-    *   `dataplex_lookup_entry`: Retrieves a specific entry from Dataplex
+    *   `lookup_entry`: Retrieves a specific entry from Dataplex
         Catalog.
-    *   `dataplex_search_aspect_types`: Finds aspect types relevant to the
+    *   `search_aspect_types`: Finds aspect types relevant to the
         query.
 
 ## Firestore

internal/util/errors.go

@@ -0,0 +1,61 @@
+// Copyright 2026 Google LLC
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package util
+
+import "fmt"
+
+type ErrorCategory string
+
+const (
+	CategoryAgent  ErrorCategory = "AGENT_ERROR"
+	CategoryServer ErrorCategory = "SERVER_ERROR"
+)
+
+// ToolboxError is the interface all custom errors must satisfy
+type ToolboxError interface {
+	error
+	Category() ErrorCategory
+}
+
+// Agent Errors return 200 to the sender
+type AgentError struct {
+	Msg   string
+	Cause error
+}
+
+func (e *AgentError) Error() string { return e.Msg }
+
+func (e *AgentError) Category() ErrorCategory { return CategoryAgent }
+
+func (e *AgentError) Unwrap() error { return e.Cause }
+
+func NewAgentError(msg string, cause error) *AgentError {
+	return &AgentError{Msg: msg, Cause: cause}
+}
+
+// ClientServerError returns 4XX/5XX error code
+type ClientServerError struct {
+	Msg   string
+	Code  int
+	Cause error
+}
+
+func (e *ClientServerError) Error() string { return fmt.Sprintf("%s: %v", e.Msg, e.Cause) }
+
+func (e *ClientServerError) Category() ErrorCategory { return CategoryServer }
+
+func (e *ClientServerError) Unwrap() error { return e.Cause }
+
+func NewClientServerError(msg string, code int, cause error) *ClientServerError {
+	return &ClientServerError{Msg: msg, Code: code, Cause: cause}
+}

tests/common.go

@@ -614,8 +614,6 @@ func GetMySQLWants() (string, string, string, string) {
 // SetupPostgresSQLTable creates and inserts data into a table of tool
 // compatible with postgres-sql tool
 func SetupPostgresSQLTable(t *testing.T, ctx context.Context, pool *pgxpool.Pool, createStatement, insertStatement, tableName string, params []any) func(*testing.T) {
-
-	
 	err := pool.Ping(ctx)
 	if err != nil {
 		t.Fatalf("unable to connect to test database: %s", err)
@@ -623,10 +621,9 @@ func SetupPostgresSQLTable(t *testing.T, ctx context.Context, pool *pgxpool.Pool
 
 	// Create table
 	_, err = pool.Query(ctx, createStatement)
-	// if err != nil {
+	if err != nil {
-	// 	t.Fatalf("unable to create test table %s: %s", tableName, err)
+		t.Fatalf("unable to create test table %s: %s", tableName, err)
-	// }
+	}
-	t.Fatalf("unable to create test table %s: %s", tableName, err)
 
 	// Insert test data
 	_, err = pool.Query(ctx, insertStatement, params...)

tests/postgres/postgres_integration_test.go

@@ -94,10 +94,7 @@ func TestPostgres(t *testing.T) {
 	}
 
 	// cleanup test environment
-	// tests.CleanupPostgresTables(t, ctx, pool)
+	tests.CleanupPostgresTables(t, ctx, pool)
-	t.Cleanup(func() {
-		tests.CleanupPostgresTables(t, context.Background(), pool)
-	})
 
 	// create table name with UUID
 	tableNameParam := "param_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")