feat: Implement Copillot CLI's Plan mode

package.json

@@ -4540,6 +4540,14 @@
 							"advanced"
 						]
 					},
+					"github.copilot.chat.cli.aiGenerateBranchNames.enabled": {
+						"type": "boolean",
+						"default": false,
+						"markdownDescription": "%github.copilot.config.cli.aiGenerateBranchNames.enabled%",
+						"tags": [
+							"advanced"
+						]
+					},
 					"github.copilot.chat.cli.forkSessions.enabled": {
 						"type": "boolean",
 						"default": false,

package.nls.json

@@ -404,6 +404,7 @@
 	"github.copilot.config.cli.branchSupport.enabled": "Enable branch support for Copilot CLI.",
 	"github.copilot.config.cli.forkSessions.enabled": "Enable forking sessions in Copilot CLI.",
 	"github.copilot.config.cli.planExitMode.enabled": "Enable Plan Mode exit handling in Copilot CLI.",
+	"github.copilot.config.cli.aiGenerateBranchNames.enabled": "Enable AI-generated branch names in Copilot CLI.",
 	"github.copilot.config.cli.isolationOption.enabled": "Enable the isolation mode option for Copilot CLI. When enabled, users can choose between Worktree and Workspace modes.",
 	"github.copilot.config.cli.autoCommit.enabled": "Enable automatic commit for Copilot CLI. When enabled, changes made by Copilot CLI will be automatically committed to the repository at the end of each turn.",
 	"github.copilot.config.cli.sessionController.enabled": "Enable the new session controller API for Copilot CLI. Requires VS Code reload.",

src/extension/chatSessions/copilotcli/node/copilotcliSession.ts

@@ -472,20 +472,25 @@ export class CopilotCLISession extends DisposableStore implements ICopilotCLISes
 						this._sdkSession.respondToExitPlanMode(event.data.requestId, { approved: false });
 						return;
 					}
-					const actionDescriptions: Record<ActionType, string> = {
-						'autopilot': l10n.t('Auto-approve all tool calls and continue until the task is done'),
-						'interactive': l10n.t('Let the agent continue in interactive mode, asking for user input and approval for each action.'),
-						'exit_only': l10n.t('Exit plan mode, but do not execute the plan. I will execute the plan myself after reviewing it.'),
-						'autopilot_fleet': l10n.t('Auto-approve all tool calls, including fleet management actions, and continue until the task is done.'),
-					};
+					const actionDescriptions: Record<string, { label: string; description: string }> = {
+						'autopilot': { label: 'Autopilot', description: l10n.t('Auto-approve all tool calls and continue until the task is done') },
+						'interactive': { label: 'Interactive', description: l10n.t('Let the agent continue in interactive mode, asking for input and approval for each action.') },
+						'exit_only': { label: 'Approve and exit', description: l10n.t('Exit planning, but do not execute the plan. I will execute the plan myself.') },
+						'autopilot_fleet': { label: 'Autopilot Fleet', description: l10n.t('Auto-approve all tool calls, including fleet management actions, and continue until the task is done.') },
+					} satisfies Record<ActionType, { label: string; description: string }>;
 
 					const approved = true;
-					event.data.actions;
 					try {
+						const planPath = this._sdkSession.getPlanPath();
+
 						const userInputRequest: IQuestion = {
-							question: l10n.t('Approve this plan?'),
+							question: planPath ? l10n.t('Approve this plan {0}?', `[Plan.md](${Uri.file(planPath).toString()})`) : l10n.t('Approve this plan?'),
 							header: l10n.t('Approve this plan?'),
-							options: event.data.actions.map(a => ({ label: (actionDescriptions as Record<string, string>)[a] ?? a, recommended: a === event.data.recommendedAction })),
+							options: event.data.actions.map(a => ({
+								label: actionDescriptions[a]?.label ?? a,
+								recommended: a === event.data.recommendedAction,
+								description: actionDescriptions[a]?.description ?? '',
+							})),
 							allowFreeformInput: true,
 						};
 						const answer = await this._userQuestionHandler.askUserQuestion(userInputRequest, this._toolInvocationToken as unknown as never, token);
@@ -498,8 +503,8 @@ export class CopilotCLISession extends DisposableStore implements ICopilotCLISes
 							this._sdkSession.respondToExitPlanMode(event.data.requestId, { approved: false, feedback: answer.freeText });
 						} else {
 							let selectedAction: ActionType = answer.selected[0] as ActionType;
-							Object.entries(actionDescriptions).forEach(([action, description]) => {
-								if (description === selectedAction) {
+							Object.entries(actionDescriptions).forEach(([action, item]) => {
+								if (item.label === selectedAction) {
 									selectedAction = action as ActionType;
 								}
 							});

src/extension/chatSessions/copilotcli/node/test/copilotcliSession.spec.ts

@@ -132,6 +132,7 @@ class MockSdkSession {
 	async getSelectedModel() { return this._selectedModel; }
 	async setSelectedModel(model: string) { this._selectedModel = model; }
 	async getEvents() { return []; }
+	getPlanPath(): string | null { return null; }
 }
 
 function createWorkspaceService(root: string): IWorkspaceService {

src/extension/chatSessions/vscode-node/askUserQuestionHandler.ts

@@ -46,7 +46,7 @@ export class UserQuestionHandler implements IUserQuestionHandler {
 		// Log all available keys in carouselAnswers for debugging
 		this._logService.trace(`[AskQuestionsTool] Question & answers ${question.question}, Answers object: ${JSON.stringify(carouselAnswers)}`);
 
-		const answer = carouselAnswers.answers[question.question];
+		const answer = carouselAnswers.answers[question.question] ?? carouselAnswers.answers[question.header];
 		if (answer === undefined) {
 			return undefined;
 		} else if (answer.freeText) {

src/extension/chatSessions/vscode-node/chatSessions.ts

@@ -190,7 +190,10 @@ export class ChatSessionsContrib extends Disposable implements IExtensionContrib
 		const gitService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(IGitService));
 		const sessionTracker = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(ICopilotCLISessionTracker));
 		const terminalIntegration = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(ICopilotCLITerminalIntegration));
-		const branchNameGenerator = copilotcliAgentInstaService.createInstance(GitBranchNameGenerator);
+		const aiGeneratedBranchNames = instantiationService.invokeFunction(accessor =>
+			accessor.get(IConfigurationService).getConfig(ConfigKey.Advanced.CLIAIGenerateBranchNames)
+		);
+		const branchNameGenerator = aiGeneratedBranchNames ? copilotcliAgentInstaService.createInstance(GitBranchNameGenerator) : undefined;
 
 		const copilotcliChatSessionParticipant = this._register(copilotcliAgentInstaService.createInstance(
 			CopilotCLIChatSessionParticipant,
@@ -260,13 +263,18 @@ export class ChatSessionsContrib extends Disposable implements IExtensionContrib
 		const gitService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(IGitService));
 		const gitExtensionService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(IGitExtensionService));
 		const toolsService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(IToolsService));
+		const aiGeneratedBranchNames = instantiationService.invokeFunction(accessor =>
+			accessor.get(IConfigurationService).getConfig(ConfigKey.Advanced.CLIAIGenerateBranchNames)
+		);
+		const branchNameGenerator = aiGeneratedBranchNames ? copilotcliAgentInstaService.createInstance(GitBranchNameGenerator) : undefined;
 
 		const copilotcliChatSessionParticipant = this._register(copilotcliAgentInstaService.createInstance(
 			CopilotCLIChatSessionParticipantV1,
 			copilotcliChatSessionContentProvider,
 			promptResolver,
 			copilotcliSessionItemProvider,
 			cloudSessionProvider,
+			branchNameGenerator
 		));
 		const copilotCLISessionService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(ICopilotCLISessionService));
 		const copilotCLIWorktreeManagerService = copilotcliAgentInstaService.invokeFunction(accessor => accessor.get(IChatSessionWorktreeService));

src/extension/chatSessions/vscode-node/copilotCLIChatSessions.ts

@@ -892,7 +892,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 		private readonly contentProvider: CopilotCLIChatSessionContentProvider,
 		private readonly promptResolver: CopilotCLIPromptResolver,
 		private readonly cloudSessionProvider: CopilotCloudSessionsProvider | undefined,
-		private readonly branchNameGenerator: GitBranchNameGenerator,
+		private readonly branchNameGenerator: GitBranchNameGenerator | undefined,
 		@IGitService private readonly gitService: IGitService,
 		@ICopilotCLIModels private readonly copilotCLIModels: ICopilotCLIModels,
 		@ICopilotCLIAgents private readonly copilotCLIAgents: ICopilotCLIAgents,
@@ -1043,7 +1043,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 				history: [requestTurn],
 				yieldRequested: false,
 			};
-			const branchNamePromise = isNewSession && request.prompt ? this.branchNameGenerator.generateBranchName(fakeContext, token) : Promise.resolve(undefined);
+			const branchNamePromise = (isNewSession && request.prompt && this.branchNameGenerator) ? this.branchNameGenerator.generateBranchName(fakeContext, token) : Promise.resolve(undefined);
 			const [model, agent] = await Promise.all([
 				this.getModelId(request, token),
 				this.getAgent(id, request, token),

src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts

@@ -6,7 +6,7 @@
 import type { Attachment, SessionOptions, SweCustomAgent } from '@github/copilot/sdk';
 import * as l10n from '@vscode/l10n';
 import * as vscode from 'vscode';
-import { ChatExtendedRequestHandler, ChatSessionProviderOptionItem, Uri } from 'vscode';
+import { ChatExtendedRequestHandler, ChatRequestTurn2, ChatSessionProviderOptionItem, Uri } from 'vscode';
 import { IRunCommandExecutionService } from '../../../platform/commands/common/runCommandExecutionService';
 import { ConfigKey, IConfigurationService } from '../../../platform/configuration/common/configurationService';
 import { INativeEnvService } from '../../../platform/env/common/envService';
@@ -33,6 +33,7 @@ import { StopWatch } from '../../../util/vs/base/common/stopwatch';
 import { URI } from '../../../util/vs/base/common/uri';
 import { EXTENSION_ID } from '../../common/constants';
 import { ChatVariablesCollection, extractDebugTargetSessionIds, isPromptFile } from '../../prompt/common/chatVariablesCollection';
+import { GitBranchNameGenerator } from '../../prompt/node/gitBranch';
 import { IToolsService } from '../../tools/common/toolsService';
 import { IChatSessionMetadataStore, RepositoryProperties, StoredModeInstructions } from '../common/chatSessionMetadataStore';
 import { IChatSessionWorkspaceFolderService } from '../common/chatSessionWorkspaceFolderService';
@@ -1094,6 +1095,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 		private readonly promptResolver: CopilotCLIPromptResolver,
 		private readonly sessionItemProvider: CopilotCLIChatSessionItemProvider,
 		private readonly cloudSessionProvider: CopilotCloudSessionsProvider | undefined,
+		private readonly branchNameGenerator: GitBranchNameGenerator | undefined,
 		@IGitService private readonly gitService: IGitService,
 		@ICopilotCLIModels private readonly copilotCLIModels: ICopilotCLIModels,
 		@ICopilotCLIAgents private readonly copilotCLIAgents: ICopilotCLIAgents,
@@ -1302,12 +1304,18 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 				return {};
 			}
 
+			const requestTurn = new ChatRequestTurn2(request.prompt ?? '', request.command, [], '', [], [], undefined, undefined, undefined);
+			const fakeContext: vscode.ChatContext = {
+				history: [requestTurn],
+				yieldRequested: false,
+			};
+			const branchNamePromise = (isUntitled && request.prompt && this.branchNameGenerator) ? this.branchNameGenerator.generateBranchName(fakeContext, token) : Promise.resolve(undefined);
 			const [model, agent] = await Promise.all([
 				this.getModelId(request, token),
 				this.getAgent(id, request, token),
 			]);
 
-			const sessionResult = await this.getOrCreateSession(request, chatSessionContext, stream, { model, agent }, disposables, token);
+			const sessionResult = await this.getOrCreateSession(request, chatSessionContext, stream, { model, agent, branchName: branchNamePromise }, disposables, token);
 			const session = sessionResult.session;
 			if (session) {
 				disposables.add(session);
@@ -1365,7 +1373,10 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 			} else {
 				// Construct the full prompt with references to be sent to CLI.
 				const { prompt, attachments } = await this.promptResolver.resolvePrompt(request, undefined, [], session.object.workspace, [], token);
-				await session.object.handleRequest(request, { prompt }, attachments, model, authInfo, token);
+				const input = (request.command && (copilotCLICommands as readonly string[]).includes(request.command))
+					? { command: request.command as CopilotCLICommand, prompt }
+					: { prompt: prompt };
+				await session.object.handleRequest(request, input, attachments, model, authInfo, token);
 				await this.commitWorktreeChangesIfNeeded(request, session.object, token);
 			}
 
@@ -1671,13 +1682,13 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 		}
 	}
 
-	private async getOrCreateSession(request: vscode.ChatRequest, chatSessionContext: vscode.ChatSessionContext, stream: vscode.ChatResponseStream, options: { model: string | undefined; agent: SweCustomAgent | undefined }, disposables: DisposableStore, token: vscode.CancellationToken): Promise<{ session: IReference<ICopilotCLISession> | undefined; trusted: boolean }> {
+	private async getOrCreateSession(request: vscode.ChatRequest, chatSessionContext: vscode.ChatSessionContext, stream: vscode.ChatResponseStream, options: { model: string | undefined; agent: SweCustomAgent | undefined; branchName: Promise<string | undefined> }, disposables: DisposableStore, token: vscode.CancellationToken): Promise<{ session: IReference<ICopilotCLISession> | undefined; trusted: boolean }> {
 		const { resource } = chatSessionContext.chatSessionItem;
 		const existingSessionId = this.sessionItemProvider.untitledSessionIdMapping.get(SessionIdForCLI.parse(resource));
 		const id = existingSessionId ?? SessionIdForCLI.parse(resource);
 		const isNewSession = chatSessionContext.isUntitled && !existingSessionId;
 
-		const { workspaceInfo, cancelled, trusted } = await this.getOrInitializeWorkingDirectory(chatSessionContext, stream, request.toolInvocationToken, token);
+		const { workspaceInfo, cancelled, trusted } = await this.getOrInitializeWorkingDirectory(chatSessionContext, options.branchName, stream, request.toolInvocationToken, token);
 		const workingDirectory = getWorkingDirectory(workspaceInfo);
 		const worktreeProperties = workspaceInfo.worktreeProperties;
 		if (cancelled || token.isCancellationRequested) {
@@ -1752,6 +1763,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 
 	private async getOrInitializeWorkingDirectory(
 		chatSessionContext: vscode.ChatSessionContext | undefined,
+		branchName: Promise<string | undefined>,
 		stream: vscode.ChatResponseStream,
 		toolInvocationToken: vscode.ChatParticipantToolToken,
 		token: vscode.CancellationToken
@@ -1770,7 +1782,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 				// Use FolderRepositoryManager to initialize folder/repository with worktree creation
 				const branch = _sessionBranch.get(id);
 				const isolation = _sessionIsolation.get(id) ?? undefined;
-				folderInfo = await this.folderRepositoryManager.initializeFolderRepository(id, { stream, toolInvocationToken, branch: branch ?? undefined, isolation, folder: undefined }, token);
+				folderInfo = await this.folderRepositoryManager.initializeFolderRepository(id, { stream, toolInvocationToken, branch: branch ?? undefined, isolation, folder: undefined, newBranch: branchName }, token);
 			} else {
 				// Existing session - use getFolderRepository for resolution with trust check
 				folderInfo = await this.folderRepositoryManager.getFolderRepository(id, { promptForTrust: true, stream }, token);
@@ -1821,7 +1833,7 @@ export class CopilotCLIChatSessionParticipant extends Disposable {
 		})();
 
 		const [{ workspaceInfo, cancelled }, model, agent] = await Promise.all([
-			this.getOrInitializeWorkingDirectory(undefined, stream, request.toolInvocationToken, token),
+			this.getOrInitializeWorkingDirectory(undefined, Promise.resolve(undefined), stream, request.toolInvocationToken, token),
 			this.getModelId(request, token), // prefer model in request, as we're delegating from another session here.
 			this.getAgent(undefined, undefined, token)
 		]);

src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts

@@ -410,6 +410,7 @@ describe('CopilotCLIChatSessionParticipant.handleRequest', () => {
 			promptResolver,
 			itemProvider,
 			cloudProvider,
+			undefined,
 			git,
 			models as unknown as ICopilotCLIModels,
 			new NullCopilotCLIAgents(),
@@ -758,6 +759,7 @@ describe('CopilotCLIChatSessionParticipant.handleRequest', () => {
 			promptResolver,
 			itemProvider,
 			cloudProvider,
+			undefined,
 			git,
 			models as unknown as ICopilotCLIModels,
 			new NullCopilotCLIAgents(),
@@ -1904,6 +1906,7 @@ describe('CopilotCLIChatSessionParticipant.handleRequest', () => {
 				promptResolver,
 				itemProvider,
 				cloudProvider,
+				undefined,
 				git,
 				models as unknown as ICopilotCLIModels,
 				agents,
@@ -2036,6 +2039,7 @@ describe('CopilotCLIChatSessionParticipant.handleRequest', () => {
 				promptResolver,
 				itemProvider,
 				cloudProvider,
+				undefined,
 				git,
 				models as unknown as ICopilotCLIModels,
 				new NullCopilotCLIAgents(),

src/platform/configuration/common/configurationService.ts

@@ -610,6 +610,7 @@ export namespace ConfigKey {
 		export const UseResponsesApiTruncation = defineAndMigrateSetting<boolean | undefined>('chat.advanced.useResponsesApiTruncation', 'chat.useResponsesApiTruncation', false);
 		export const OmitBaseAgentInstructions = defineAndMigrateSetting<boolean>('chat.advanced.omitBaseAgentInstructions', 'chat.omitBaseAgentInstructions', false);
 		export const CLIPlanExitModeEnabled = defineSetting<boolean>('chat.cli.planExitMode.enabled', ConfigType.Simple, false);
+		export const CLIAIGenerateBranchNames = defineSetting<boolean>('chat.cli.aiGenerateBranchNames.enabled', ConfigType.Simple, false);
 		export const CLIForkSessionsEnabled = defineSetting<boolean>('chat.cli.forkSessions.enabled', ConfigType.Simple, false);
 		export const CLIMCPServerEnabled = defineAndMigrateSetting<boolean | undefined>('chat.advanced.cli.mcp.enabled', 'chat.cli.mcp.enabled', true);
 		export const CLIBranchSupport = defineSetting<boolean>('chat.cli.branchSupport.enabled', ConfigType.Simple, false);