diff --git a/extensions/copilot/src/extension/tools/node/abstractReplaceStringTool.tsx b/extensions/copilot/src/extension/tools/node/abstractReplaceStringTool.tsx
index 708f19c0c5a..4042bae46b7 100644
--- a/extensions/copilot/src/extension/tools/node/abstractReplaceStringTool.tsx
+++ b/extensions/copilot/src/extension/tools/node/abstractReplaceStringTool.tsx
@@ -28,7 +28,7 @@ import { ResourceMap, ResourceSet } from '../../../util/vs/base/common/map';
 import { isDefined } from '../../../util/vs/base/common/types';
 import { URI } from '../../../util/vs/base/common/uri';
 import { IInstantiationService } from '../../../util/vs/platform/instantiation/common/instantiation';
-import { ChatRequestEditorData, ChatResponseTextEditPart, EndOfLine, Position as ExtPosition, LanguageModelPromptTsxPart, LanguageModelToolResult, TextEdit } from '../../../vscodeTypes';
+import { ChatRequestEditorData, ChatResponseTextEditPart, EndOfLine, ExtendedLanguageModelToolResult, Position as ExtPosition, LanguageModelPromptTsxPart, LanguageModelToolResult, TextEdit } from '../../../vscodeTypes';
 import { IBuildPromptContext } from '../../prompt/common/intents';
 import { renderPromptElementJSON } from '../../prompts/node/base/promptRenderer';
 import { CellOrNotebookEdit, processFullRewriteNotebookEdits } from '../../prompts/node/codeMapper/codeMapper';
@@ -39,7 +39,7 @@ import { IToolsService } from '../common/toolsService';
 import { ActionType } from './applyPatch/parser';
 import { CorrectedEditResult, healReplaceStringParams } from './editFileHealing';
 import { EditFileResult, IEditedFile } from './editFileToolResult';
-import { EditError, NoChangeError, NoMatchError, applyEdit, canExistingFileBeEdited, createEditConfirmation, formatDiffAsUnified, logEditToolResult, openDocumentAndSnapshot } from './editFileToolUtils';
+import { applyEdit, canExistingFileBeEdited, createEditConfirmation, EditError, formatDiffAsUnified, logEditToolResult, NoChangeError, NoMatchError, openDocumentAndSnapshot } from './editFileToolUtils';
 import { sendEditNotebookTelemetry } from './editNotebookTool';
 import { assertFileNotContentExcluded, resolveToolInputPath } from './toolUtils';
 
@@ -308,7 +308,7 @@ export abstract class AbstractReplaceStringTool<T extends { explanation: string
 
 		const isInlineChat = this._promptContext.request?.location2 instanceof ChatRequestEditorData;
 
-		return new LanguageModelToolResult([
+		const result = new ExtendedLanguageModelToolResult([
 			new LanguageModelPromptTsxPart(
 				await renderPromptElementJSON(
 					this.instantiationService,
@@ -324,6 +324,9 @@ export abstract class AbstractReplaceStringTool<T extends { explanation: string
 				),
 			)
 		]);
+
+		result.hasError = fileResults.some(f => f.error);
+		return result;
 	}
 
 	private async generateEdit(uri: URI, document: TextDocumentSnapshot | NotebookDocumentSnapshot, options: vscode.LanguageModelToolInvocationOptions<T> | vscode.LanguageModelToolInvocationPrepareOptions<T>, input: IAbstractReplaceStringInput, didHealRef: { healed?: IAbstractReplaceStringInput }, token: vscode.CancellationToken) {
diff --git a/extensions/copilot/src/extension/tools/node/applyPatchTool.tsx b/extensions/copilot/src/extension/tools/node/applyPatchTool.tsx
index 8dfe38428ef..841e60f2596 100644
--- a/extensions/copilot/src/extension/tools/node/applyPatchTool.tsx
+++ b/extensions/copilot/src/extension/tools/node/applyPatchTool.tsx
@@ -31,7 +31,7 @@ import { ResourceMap, ResourceSet } from '../../../util/vs/base/common/map';
 import { isDefined } from '../../../util/vs/base/common/types';
 import { URI } from '../../../util/vs/base/common/uri';
 import { IInstantiationService } from '../../../util/vs/platform/instantiation/common/instantiation';
-import { ChatRequestEditorData, ChatResponseTextEditPart, LanguageModelPromptTsxPart, LanguageModelTextPart, LanguageModelToolResult, Position, Range, WorkspaceEdit } from '../../../vscodeTypes';
+import { ChatRequestEditorData, ChatResponseTextEditPart, ExtendedLanguageModelToolResult, LanguageModelPromptTsxPart, LanguageModelTextPart, LanguageModelToolResult, Position, Range, WorkspaceEdit } from '../../../vscodeTypes';
 import { IBuildPromptContext } from '../../prompt/common/intents';
 import { ApplyPatchFormatInstructions } from '../../prompts/node/agent/defaultAgentInstructions';
 import { PromptRenderer, renderPromptElementJSON } from '../../prompts/node/base/promptRenderer';
@@ -417,7 +417,7 @@ export class ApplyPatchTool implements ICopilotTool<IApplyPatchToolParams> {
 			const isInlineChat = this._promptContext.request?.location2 instanceof ChatRequestEditorData;
 			const isNotebook = editEntires.length === 1 ? handledNotebookUris.size === 1 : undefined;
 			this.sendApplyPatchTelemetry('success', options, undefined, !!healed, isNotebook);
-			return new LanguageModelToolResult([
+			const result = new ExtendedLanguageModelToolResult([
 				new LanguageModelPromptTsxPart(
 					await renderPromptElementJSON(
 						this.instantiationService,
@@ -431,13 +431,17 @@ export class ApplyPatchTool implements ICopilotTool<IApplyPatchToolParams> {
 					),
 				)
 			]);
+			result.hasError = files.some(f => f.error);
+			return result;
 		} catch (error) {
 			const isNotebook = Object.values(docText).length === 1 ? (!!mapFindFirst(Object.values(docText), v => v.notebookUri)) : undefined;
 			// TODO parser.ts could annotate DiffError with a telemetry detail if we want
 			this.sendApplyPatchTelemetry('error', options, undefined, false, isNotebook, error);
-			return new LanguageModelToolResult([
+			const result = new ExtendedLanguageModelToolResult([
 				new LanguageModelTextPart('Applying patch failed with error: ' + error.message),
 			]);
+			result.hasError = true;
+			return result;
 		}
 	}
 
diff --git a/extensions/copilot/src/extension/vscode.proposed.chatParticipantPrivate.d.ts b/extensions/copilot/src/extension/vscode.proposed.chatParticipantPrivate.d.ts
index 398dce07fdd..9f9d0a4b6a9 100644
--- a/extensions/copilot/src/extension/vscode.proposed.chatParticipantPrivate.d.ts
+++ b/extensions/copilot/src/extension/vscode.proposed.chatParticipantPrivate.d.ts
@@ -248,6 +248,8 @@ declare module 'vscode' {
 		toolResultMessage?: string | MarkdownString;
 		toolResultDetails?: Array<Uri | Location>;
 		toolMetadata?: unknown;
+		/** Whether there was an error calling the tool. The tool may still have partially succeeded. */
+		hasError?: boolean;
 	}
 
 	// #region Chat participant detection