diff --git a/src/@types/vscode.proposed.chatParticipantAdditions.d.ts b/src/@types/vscode.proposed.chatParticipantAdditions.d.ts
index f05e4fe691..f4ce44cd9e 100644
--- a/src/@types/vscode.proposed.chatParticipantAdditions.d.ts
+++ b/src/@types/vscode.proposed.chatParticipantAdditions.d.ts
@@ -167,7 +167,14 @@ declare module 'vscode' {
 		constructor(value: ChatResponseDiffEntry[], title: string, readOnly?: boolean);
 	}
 
-	export type ExtendedChatResponsePart = ChatResponsePart | ChatResponseTextEditPart | ChatResponseNotebookEditPart | ChatResponseConfirmationPart | ChatResponseCodeCitationPart | ChatResponseReferencePart2 | ChatResponseMovePart | ChatResponseExtensionsPart | ChatResponsePullRequestPart | ChatPrepareToolInvocationPart | ChatToolInvocationPart | ChatResponseMultiDiffPart | ChatResponseThinkingProgressPart;
+	export class ChatResponseExternalEditPart {
+		uris: Uri[];
+		callback: () => Thenable<unknown>;
+		applied: Thenable<void>;
+		constructor(uris: Uri[], callback: () => Thenable<unknown>);
+	}
+
+	export type ExtendedChatResponsePart = ChatResponsePart | ChatResponseTextEditPart | ChatResponseNotebookEditPart | ChatResponseConfirmationPart | ChatResponseCodeCitationPart | ChatResponseReferencePart2 | ChatResponseMovePart | ChatResponseExtensionsPart | ChatResponsePullRequestPart | ChatPrepareToolInvocationPart | ChatToolInvocationPart | ChatResponseMultiDiffPart | ChatResponseThinkingProgressPart | ChatResponseExternalEditPart;
 	export class ChatResponseWarningPart {
 		value: MarkdownString;
 		constructor(value: string | MarkdownString);
@@ -301,6 +308,14 @@ declare module 'vscode' {
 
 		notebookEdit(target: Uri, isDone: true): void;
 
+		/**
+		 * Makes an external edit to one or more resources. Changes to the
+		 * resources made within the `callback` and before it resolves will be
+		 * tracked as agent edits. This can be used to track edits made from
+		 * external tools that don't generate simple {@link textEdit textEdits}.
+		 */
+		externalEdit<T>(target: Uri | Uri[], callback: () => Thenable<T>): Thenable<T>;
+
 		markdownWithVulnerabilities(value: string | MarkdownString, vulnerabilities: ChatVulnerability[]): void;
 		codeblockUri(uri: Uri, isEdit?: boolean): void;
 		push(part: ChatResponsePart | ChatResponseTextEditPart | ChatResponseWarningPart | ChatResponseProgressPart2): void;
diff --git a/src/@types/vscode.proposed.chatParticipantPrivate.d.ts b/src/@types/vscode.proposed.chatParticipantPrivate.d.ts
index dca0f364d7..398dce07fd 100644
--- a/src/@types/vscode.proposed.chatParticipantPrivate.d.ts
+++ b/src/@types/vscode.proposed.chatParticipantPrivate.d.ts
@@ -87,6 +87,8 @@ declare module 'vscode' {
 		 * Events for edited files in this session collected since the last request.
 		 */
 		readonly editedFileEvents?: ChatRequestEditedFileEvent[];
+
+		readonly isSubagent?: boolean;
 	}
 
 	export enum ChatRequestEditedFileEventKind {
diff --git a/src/view/reviewManager.ts b/src/view/reviewManager.ts
index 6260047828..ec6ef2c0ae 100644
--- a/src/view/reviewManager.ts
+++ b/src/view/reviewManager.ts
@@ -16,6 +16,7 @@ import { ProgressHelper } from './progress';
 import { PullRequestsTreeDataProvider } from './prsTreeDataProvider';
 import { ReviewCommentController, SuggestionInformation } from './reviewCommentController';
 import { ReviewModel } from './reviewModel';
+import { COPILOT_SWE_AGENT } from '../common/copilot';
 import { DiffChangeType, DiffHunk, parsePatch, splitIntoSmallerHunks } from '../common/diffHunk';
 import { commands } from '../common/executeCommands';
 import { GitChangeType, InMemFileChange, SlimFileChange } from '../common/file';
@@ -1142,9 +1143,11 @@ export class ReviewManager extends Disposable {
 			this._upgradePullRequestEditors(pr);
 
 			/* __GDPR__
-				"pr.checkout" : {}
+				"pr.checkout" : {
+					"isCopilot" : { "classification": "SystemMetaData", "purpose": "FeatureInsight" }
+				}
 			*/
-			this._telemetry.sendTelemetryEvent('pr.checkout');
+			this._telemetry.sendTelemetryEvent('pr.checkout', { isCopilot: (pr.author.login === COPILOT_SWE_AGENT) ? 'true' : 'false' });
 			Logger.appendLine(`Switch to Pull Request #${pr.number} - done`, this.id);
 		} finally {
 			this.setStatusForPr(pr);
diff --git a/src/view/reviewsManager.ts b/src/view/reviewsManager.ts
index 2995e0c8a8..1143b0efb2 100644
--- a/src/view/reviewsManager.ts
+++ b/src/view/reviewsManager.ts
@@ -11,6 +11,7 @@ import { PrsTreeModel } from './prsTreeModel';
 import { ReviewManager } from './reviewManager';
 import { Repository } from '../api/api';
 import { GitApiImpl, Status } from '../api/api1';
+import { COPILOT_SWE_AGENT } from '../common/copilot';
 import { Disposable } from '../common/lifecycle';
 import * as PersistentState from '../common/persistentState';
 import { ITelemetry } from '../common/telemetry';
@@ -120,10 +121,11 @@ export class ReviewsManager extends Disposable {
 
 		/* __GDPR__
 			"pr.checkout" : {
-				"fromDescriptionPage" : { "classification": "SystemMetaData", "purpose": "FeatureInsight" }
+				"fromDescription" : { "classification": "SystemMetaData", "purpose": "FeatureInsight" },
+				"isCopilot" : { "classification": "SystemMetaData", "purpose": "FeatureInsight" }
 			}
 		*/
-		this._telemetry.sendTelemetryEvent('pr.checkout', { fromDescription: isFromDescription.toString() });
+		this._telemetry.sendTelemetryEvent('pr.checkout', { fromDescription: isFromDescription.toString(), isCopilot: (pullRequestModel.author.login === COPILOT_SWE_AGENT) ? 'true' : 'false' });
 
 		return vscode.window.withProgress(
 			{