Update chat in editor titles after rename tool

src/vs/workbench/contrib/chat/browser/agentSessions/agentHost/agentHostSessionHandler.ts

@@ -588,6 +588,13 @@ function inputRequestResponsePartKey(part: InputRequestResponsePart): string {
 	return `ir:${part.request.id}:${JSON.stringify({ ...part.request, answers: undefined })}`;
 }
 
+function getChatTitle(state: Pick<SessionState, 'chats' | 'defaultChat' | 'title'>, chatURI: string): string {
+	if (state.defaultChat === chatURI && state.chats.length === 1) {
+		return state.title;
+	}
+	return state.chats.find(chat => chat.resource === chatURI)?.title || state.title;
+}
+
 /**
  * The live invocation the reconnect snapshot emitted for this tool call, if
  * any. A tool call the snapshot rendered as a serialized part has no live
@@ -1273,7 +1280,7 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 		let initialProgress: IChatProgress[] | undefined;
 		let initialResponsePartCount = 0;
 		let activeTurnId: string | undefined;
-		let sessionTitle: string | undefined;
+		let chatTitle: string | undefined;
 		let draftInputState: ISerializableChatModelInputState | undefined;
 		let sessionSubscription: IAgentSubscription<SessionState> | undefined;
 		let chatSubscription: IAgentSubscription<ChatState> | undefined;
@@ -1315,7 +1322,7 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 					await this._whenSubscriptionHydrated(chatSub, token);
 					const sessionState = this._getSessionState(resolvedSession.toString(), chatURI);
 					if (sessionState) {
-						sessionTitle = sessionState.title;
+						chatTitle = getChatTitle(sessionState, chatURI);
 						const draft = sessionState.draft ?? emptyDraftFromLastTurn(sessionState);
 						draftInputState = this._draftToInputState(sessionResource, draft);
 						if (!sessionState.draft && draft) {
@@ -1437,7 +1444,7 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 				AgentHostChatSession,
 				sessionResource,
 				history,
-				sessionTitle,
+				chatTitle,
 				sessionSubscription,
 				chatSubscription,
 				this._config.promptCacheNotification,
@@ -2095,7 +2102,7 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 		let lastSeenTurnId: string | undefined = currentState?.activeTurn?.id;
 		let previousQueuedIds: Set<string> | undefined;
 		let previousSteeringId: string | undefined = currentState?.steeringMessage?.id;
-		let previousTitle: string | undefined = currentState?.title;
+		let previousTitle: string | undefined = currentState ? getChatTitle(currentState, chatURI) : undefined;
 
 		const disposables = new DisposableStore();
 
@@ -2105,9 +2112,8 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 
 		const sessionSub = this._ensureSessionSubscription(sessionStr);
 		const chatSub = this._ensureChatSubscription(sessionStr, chatURI);
-		// Conversation contents now live on the default chat, while title and
-		// other session-scoped fields stay on the session. Re-evaluate on a
-		// change to either channel, reading the merged view.
+		// Conversation contents live on the chat, while its catalog title and
+		// other session-scoped fields live on the session. Re-evaluate on either.
 		const onChange = () => {
 			const state = this._getSessionState(sessionStr, chatURI);
 			if (!state) {
@@ -2125,7 +2131,7 @@ export class AgentHostSessionHandler extends Disposable implements IChatSessionC
 			}
 			previousSteeringId = currentSteeringId;
 
-			const currentTitle = e.state.title;
+			const currentTitle = getChatTitle(e.state, chatURI);
 			if (currentTitle && currentTitle !== previousTitle) {
 				this._chatService.setChatSessionTitle(sessionResource, currentTitle);
 			}

src/vs/workbench/contrib/chat/browser/agentSessions/agentHost/agentHostSessionListStore.ts

@@ -9,14 +9,15 @@ import { Disposable } from '../../../../../../base/common/lifecycle.js';
 import { extUriBiasedIgnorePathCase } from '../../../../../../base/common/resources.js';
 import { URI } from '../../../../../../base/common/uri.js';
 import { AgentSession, type IAgentSessionMetadata } from '../../../../../../platform/agentHost/common/agentService.js';
-import { ActionType, type IIsArchivedChangedAction, type IIsReadChangedAction, type INotification, type SessionAction } from '../../../../../../platform/agentHost/common/state/sessionActions.js';
-import { readSessionEhcliAdoptable, readSessionMultiRootMetadata, SessionStatus, type SessionSummary } from '../../../../../../platform/agentHost/common/state/sessionState.js';
+import { ActionType, type ActionEnvelope, type IIsArchivedChangedAction, type IIsReadChangedAction, type INotification, type SessionAction } from '../../../../../../platform/agentHost/common/state/sessionActions.js';
+import { isDefaultChatUri, readSessionEhcliAdoptable, readSessionMultiRootMetadata, SessionStatus, type SessionSummary } from '../../../../../../platform/agentHost/common/state/sessionState.js';
 import { IWorkspaceContextService, type IWorkspaceFolder } from '../../../../../../platform/workspace/common/workspace.js';
 
 /**
  * Minimal agent-host connection surface needed by the session list store.
  */
 export interface IAgentHostSessionListConnection {
+	readonly onDidAction: Event<ActionEnvelope>;
 	readonly onDidNotification: Event<INotification>;
 	listSessions(): Promise<IAgentSessionMetadata[]>;
 	disposeSession(session: URI): Promise<void>;
@@ -61,9 +62,9 @@ export interface IAgentHostSessionListDelta {
 
 /**
  * Shared provider-agnostic cache of agent-host sessions. It owns the
- * provider-wide listSessions refresh, workspace filtering, and root session
- * notifications. Per-provider list controllers project this state into chat
- * session items.
+ * provider-wide listSessions refresh, workspace filtering, session
+ * notifications, and live title actions. Per-provider list controllers project
+ * this state into chat session items.
  */
 export class AgentHostSessionListStore extends Disposable {
 
@@ -94,6 +95,7 @@ export class AgentHostSessionListStore extends Disposable {
 	) {
 		super();
 
+		this._register(this._connection.onDidAction(e => this._onAction(e)));
 		this._register(this._connection.onDidNotification(n => this._onNotification(n)));
 
 		// Re-fetch the session list whenever the set of VS Code workspace
@@ -326,6 +328,40 @@ export class AgentHostSessionListStore extends Disposable {
 		}
 	}
 
+	private _onAction(envelope: ActionEnvelope): void {
+		if (envelope.rejectionReason !== undefined) {
+			return;
+		}
+		const action = envelope.action;
+		const title = action.type === ActionType.SessionTitleChanged
+			? action.title
+			: action.type === ActionType.SessionChatUpdated && isDefaultChatUri(action.chat) && action.changes.title !== undefined
+				? action.changes.title
+				: undefined;
+		if (!title) {
+			return;
+		}
+
+		const provider = AgentSession.provider(envelope.channel);
+		if (!provider) {
+			return;
+		}
+		const rawId = AgentSession.id(envelope.channel);
+		const key = this._key(provider, rawId);
+		const cached = this._entries.get(key);
+		if (!cached || cached.summary.title === title) {
+			return;
+		}
+
+		const updated: IAgentHostSessionListEntry = {
+			...cached,
+			summary: { ...cached.summary, title },
+		};
+		this._mutationGeneration++;
+		this._entries.set(key, updated);
+		this._onDidChangeSessions.fire({ addedOrUpdated: [updated] });
+	}
+
 	private _makeEntryFromMetadata(session: IAgentSessionMetadata): IAgentHostSessionListEntry | undefined {
 		const provider = AgentSession.provider(session.session);
 		if (!provider) {

src/vs/workbench/contrib/chat/test/browser/agentSessions/agentHostChatContribution.test.ts

@@ -818,6 +818,10 @@ function createTestServices(disposables: DisposableStore, workingDirectoryResolv
 		removePendingRequest(sessionResource: URI, requestId: string) {
 			this.removePendingRequestCalls.push({ sessionResource, requestId });
 		},
+		setChatSessionTitleCalls: [] as { sessionResource: URI; title: string }[],
+		async setChatSessionTitle(sessionResource: URI, title: string) {
+			this.setChatSessionTitleCalls.push({ sessionResource, title });
+		},
 		syncPendingRequestsFromRemoteCalls: [] as { sessionResource: URI; requests: readonly IRemotePendingRequest[] }[],
 		/** Set by tests that want to mirror remote pending messages into their fake chat model. */
 		applyRemotePendingRequests: undefined as ((sessionResource: URI, requests: readonly IRemotePendingRequest[]) => void) | undefined,
@@ -2950,6 +2954,60 @@ suite('AgentHostChatContribution', () => {
 			});
 		});
 
+		test('session and default chat title actions update the session list item', async () => {
+			const { instantiationService, agentHostService } = createTestServices(disposables);
+			const backendSession = AgentSession.uri('copilot', 'chat-title');
+			agentHostService.addSession({ session: backendSession, startTime: 1000, modifiedTime: 2000, summary: 'Session title' });
+
+			const sessionListStore = createSessionListStore(disposables, instantiationService, agentHostService);
+			const listController = disposables.add(instantiationService.createInstance(AgentHostSessionListController, 'agent-host-copilot', 'copilot', sessionListStore, undefined, 'local'));
+			await listController.refresh(CancellationToken.None);
+
+			const events: string[] = [];
+			disposables.add(listController.onDidChangeChatSessionItems(delta => {
+				events.push(...(delta.addedOrUpdated ?? []).map(item => item.label));
+			}));
+
+			agentHostService.fireAction({
+				channel: backendSession.toString(),
+				action: {
+					type: ActionType.SessionTitleChanged,
+					title: 'Renamed session',
+				},
+				serverSeq: 1,
+				origin: undefined,
+			});
+			agentHostService.fireAction({
+				channel: backendSession.toString(),
+				action: {
+					type: ActionType.SessionChatUpdated,
+					chat: buildDefaultChatUri(backendSession.toString()),
+					changes: { title: 'Renamed default chat' },
+				},
+				serverSeq: 2,
+				origin: undefined,
+			});
+			agentHostService.fireAction({
+				channel: backendSession.toString(),
+				action: {
+					type: ActionType.SessionChatUpdated,
+					chat: buildDefaultChatUri(backendSession.toString()),
+					changes: { title: 'Rejected title' },
+				},
+				serverSeq: 3,
+				origin: { clientId: agentHostService.clientId, clientSeq: 1 },
+				rejectionReason: 'Rename rejected',
+			});
+
+			assert.deepStrictEqual({
+				label: listController.items[0].label,
+				events,
+			}, {
+				label: 'Renamed default chat',
+				events: ['Renamed session', 'Renamed default chat'],
+			});
+		});
+
 		test('sessionRemoved notification removes only the matching item', async () => {
 			const { instantiationService, agentHostService } = createTestServices(disposables);
 
@@ -10028,6 +10086,103 @@ suite('AgentHostChatContribution', () => {
 			};
 		}
 
+		test('uses independent default chat titles for the editor', async () => {
+			const { sessionHandler, agentHostService, chatService } = createContribution(disposables);
+			const backendSession = AgentSession.uri('copilot', 'independent-chat-title');
+			const sessionResource = URI.from({ scheme: 'agent-host-copilot', path: '/independent-chat-title' });
+			const defaultChat = buildDefaultChatUri(backendSession.toString());
+			const peerChat = buildChatUri(backendSession.toString(), 'peer');
+			const summary: SessionSummary = {
+				resource: backendSession.toString(),
+				provider: 'copilot',
+				title: 'Session title',
+				status: SessionStatus.Idle,
+				createdAt: new Date().toISOString(),
+				modifiedAt: new Date().toISOString(),
+			};
+			agentHostService.sessionStates.set(backendSession.toString(), {
+				...createSessionState(summary),
+				lifecycle: SessionLifecycle.Ready,
+				defaultChat,
+				chats: [
+					{ ...createDefaultChatSummary(summary, defaultChat), title: 'Default chat title' },
+					{ ...createDefaultChatSummary(summary, peerChat), title: 'Peer chat title' },
+				],
+			});
+
+			const chatSession = await sessionHandler.provideChatSessionContent(sessionResource, CancellationToken.None);
+			disposables.add(toDisposable(() => chatSession.dispose()));
+
+			agentHostService.fireAction({
+				channel: backendSession.toString(),
+				action: {
+					type: ActionType.SessionChatUpdated,
+					chat: defaultChat,
+					changes: { title: 'Renamed default chat' },
+				},
+				serverSeq: 1,
+				origin: undefined,
+			});
+
+			assert.deepStrictEqual({
+				initialTitle: chatSession.title,
+				titleChanges: chatService.setChatSessionTitleCalls.map(call => ({
+					sessionResource: call.sessionResource.toString(),
+					title: call.title,
+				})),
+			}, {
+				initialTitle: 'Default chat title',
+				titleChanges: [{
+					sessionResource: sessionResource.toString(),
+					title: 'Renamed default chat',
+				}],
+			});
+		});
+
+		test('uses the session title for a sole default chat', async () => {
+			const { sessionHandler, agentHostService, chatService } = createContribution(disposables);
+			const backendSession = AgentSession.uri('copilot', 'sole-chat-title');
+			const sessionResource = URI.from({ scheme: 'agent-host-copilot', path: '/sole-chat-title' });
+			agentHostService.sessionStates.set(backendSession.toString(), {
+				...createSessionState({
+					resource: backendSession.toString(),
+					provider: 'copilot',
+					title: 'Original session title',
+					status: SessionStatus.Idle,
+					createdAt: new Date().toISOString(),
+					modifiedAt: new Date().toISOString(),
+				}),
+				lifecycle: SessionLifecycle.Ready,
+			});
+
+			const chatSession = await sessionHandler.provideChatSessionContent(sessionResource, CancellationToken.None);
+			disposables.add(toDisposable(() => chatSession.dispose()));
+
+			agentHostService.fireAction({
+				channel: backendSession.toString(),
+				action: {
+					type: ActionType.SessionTitleChanged,
+					title: 'Renamed session',
+				},
+				serverSeq: 1,
+				origin: undefined,
+			});
+
+			assert.deepStrictEqual({
+				initialTitle: chatSession.title,
+				titleChanges: chatService.setChatSessionTitleCalls.map(call => ({
+					sessionResource: call.sessionResource.toString(),
+					title: call.title,
+				})),
+			}, {
+				initialTitle: 'Original session title',
+				titleChanges: [{
+					sessionResource: sessionResource.toString(),
+					title: 'Renamed session',
+				}],
+			});
+		});
+
 		test('syncs queued messages added to restored active sessions idempotently', async () => {
 			const { sessionHandler, agentHostService, chatService } = createContribution(disposables);