fix: properly report tool errors in telemetry (#5688)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/core/src/tools/shell.ts

@@ -17,6 +17,7 @@ import {
   ToolConfirmationOutcome,
   Icon,
 } from './tools.js';
+import { ToolErrorType } from './tool-error.js';
 import { Type } from '@google/genai';
 import { SchemaValidator } from '../utils/schemaValidator.js';
 import { getErrorMessage } from '../utils/errors.js';
@@ -186,8 +187,12 @@ export class ShellTool extends BaseTool<ShellToolParams, ToolResult> {
     });
     if (validationError) {
       return {
-        llmContent: validationError,
+        llmContent: `Could not execute command due to invalid parameters: ${validationError}`,
         returnDisplay: validationError,
+        error: {
+          message: validationError,
+          type: ToolErrorType.INVALID_TOOL_PARAMS,
+        },
       };
     }