chat: expose toolResultError as boolean flag (#298320)

* chat: expose toolResultError as boolean flag

Converts toolResultError to support both string and boolean types,
allowing it to be used as a simple error flag when the specific error
message is not needed. The conversion to boolean is safe because the
only usage is in a truthy check.

- Updates IToolResult interface to accept string | boolean for toolResultError
- Adds conversion logic in extHostTypeConverters for boolean mapping
- Passes the error flag through the main thread language model tools

Refs #298226

(Commit message generated by Copilot)

* fix

Author: connor4312

src/vs/workbench/api/browser/mainThreadLanguageModelTools.ts

@@ -66,7 +66,8 @@ export class MainThreadLanguageModelTools extends Disposable implements MainThre
 		// Only return content and metadata to EH
 		const out: Dto<IToolResult> = {
 			content: result.content,
-			toolMetadata: result.toolMetadata
+			toolMetadata: result.toolMetadata,
+			toolResultError: result.toolResultError,
 		};
 		return toolResultHasBuffers(result) ? new SerializableObjectWithBuffers(out) : out;
 	}

src/vs/workbench/api/common/extHostTypeConverters.ts

@@ -3873,6 +3873,9 @@ export namespace LanguageModelToolResult {
 		if (result.toolMetadata !== undefined) {
 			toolResult.toolMetadata = result.toolMetadata;
 		}
+		if (result.toolResultError) {
+			toolResult.hasError = !!result.toolResultError;
+		}
 		return toolResult;
 	}
 
@@ -3938,6 +3941,7 @@ export namespace LanguageModelToolResult {
 			toolResultMessage: MarkdownString.fromStrict(result.toolResultMessage),
 			toolResultDetails: detailsDto,
 			toolMetadata: result.toolMetadata,
+			toolResultError: result.hasError,
 		};
 
 		return hasBuffers ? new SerializableObjectWithBuffers(dto) : dto;

src/vs/workbench/contrib/chat/common/tools/languageModelToolsService.ts

@@ -265,7 +265,7 @@ export interface IToolResult {
 	content: (IToolResultPromptTsxPart | IToolResultTextPart | IToolResultDataPart)[];
 	toolResultMessage?: string | IMarkdownString;
 	toolResultDetails?: Array<URI | Location> | IToolResultInputOutputDetails | IToolResultOutputDetails;
-	toolResultError?: string;
+	toolResultError?: string | boolean;
 	toolMetadata?: unknown;
 	/** Whether to ask the user to confirm these tool results. Overrides {@link IToolConfirmationMessages.confirmResults}. */
 	confirmResults?: boolean;

src/vs/workbench/contrib/chat/test/browser/tools/languageModelToolsService.test.ts

@@ -3905,7 +3905,7 @@ suite('LanguageModelToolsService', () => {
 
 			// Verify error result returned
 			assert.ok(result.toolResultError);
-			assert.ok(result.toolResultError.includes('Destructive operations require approval'));
+			assert.ok((result.toolResultError as string).includes('Destructive operations require approval'));
 			assert.strictEqual(result.content[0].kind, 'text');
 			assert.ok((result.content[0] as IToolResultTextPart).value.includes('Tool execution denied'));