feat(chat): add /stop cancellation command across gateway and telegram

src/channels/telegram/adapter.test.ts

@@ -81,14 +81,16 @@ describe('TelegramAdapter', () => {
     // .use() for auth middleware
     expect(mockUse).toHaveBeenCalledTimes(1);
     expect(mockCatch).toHaveBeenCalledTimes(1);
-    // .command() for /start, /reset, /model, /local, /cloud, /transfer
+    // .command() for /start, /reset, /model, /local, /cloud, /transfer, /stop, /cancel
-    expect(mockCommand).toHaveBeenCalledTimes(6);
+    expect(mockCommand).toHaveBeenCalledTimes(8);
     expect(mockCommand.mock.calls[0][0]).toBe('start');
     expect(mockCommand.mock.calls[1][0]).toBe('reset');
     expect(mockCommand.mock.calls[2][0]).toBe('model');
     expect(mockCommand.mock.calls[3][0]).toBe('local');
     expect(mockCommand.mock.calls[4][0]).toBe('cloud');
     expect(mockCommand.mock.calls[5][0]).toBe('transfer');
+    expect(mockCommand.mock.calls[6][0]).toBe('stop');
+    expect(mockCommand.mock.calls[7][0]).toBe('cancel');
     // .on('message:text', ...) for text handler
     expect(mockOn).toHaveBeenCalledWith('message:text', expect.any(Function));
     // .start() to begin long polling
@@ -301,6 +303,44 @@ describe('TelegramAdapter', () => {
     });
   });
 
+  it('/stop command forwards a stop command message', async () => {
+    const handler = vi.fn();
+    adapter.onMessage(handler);
+    await adapter.connect();
+
+    const stopHandler = getCommandHandler('stop');
+    const ctx = {
+      message: { message_id: 200 },
+      chat: { id: 100 },
+      from: { first_name: 'Will' },
+    };
+    await stopHandler(ctx);
+
+    expect(handler).toHaveBeenCalledTimes(1);
+    const msg: InboundMessage = handler.mock.calls[0][0];
+    expect(msg.text).toBe('/stop');
+    expect(msg.metadata).toEqual({ isCommand: true, command: 'stop' });
+  });
+
+  it('/cancel command forwards a cancel command message', async () => {
+    const handler = vi.fn();
+    adapter.onMessage(handler);
+    await adapter.connect();
+
+    const cancelHandler = getCommandHandler('cancel');
+    const ctx = {
+      message: { message_id: 201 },
+      chat: { id: 100 },
+      from: { first_name: 'Will' },
+    };
+    await cancelHandler(ctx);
+
+    expect(handler).toHaveBeenCalledTimes(1);
+    const msg: InboundMessage = handler.mock.calls[0][0];
+    expect(msg.text).toBe('/stop');
+    expect(msg.metadata).toEqual({ isCommand: true, command: 'cancel' });
+  });
+
   // ── Auth middleware ───────────────────────────────────────────
 
   it('auth middleware blocks unauthorized chat IDs', async () => {

src/channels/telegram/adapter.ts

@@ -261,6 +261,22 @@ export class TelegramAdapter implements ChannelAdapter {
       });
     });
 
+    const handleStopCommand = (command: 'stop' | 'cancel') => async (ctx: { message?: { message_id?: number }; chat: { id: number }; from?: { first_name?: string } }) => {
+      if (!this.messageHandler) {return;}
+      this.messageHandler({
+        id: String(ctx.message?.message_id ?? Date.now()),
+        channel: 'telegram',
+        senderId: String(ctx.chat.id),
+        senderName: ctx.from?.first_name,
+        text: '/stop',
+        timestamp: Date.now(),
+        metadata: { isCommand: true, command },
+      });
+    };
+
+    bot.command('stop', handleStopCommand('stop'));
+    bot.command('cancel', handleStopCommand('cancel'));
+
     // ── Text message handler ──
 
     bot.on('message:text', async (ctx) => {
@@ -465,7 +481,7 @@ export class TelegramAdapter implements ChannelAdapter {
 
     // bot.start() is a long-running method that resolves only when the bot stops.
     // Do NOT await it — fire-and-forget so connect() resolves immediately.
-    bot.start({
+    const startResult = bot.start({
       onStart: (botInfo) => {
         console.log(`Telegram bot started: @${botInfo.username}`);
         this.botInfo = { id: botInfo.id, username: botInfo.username };
@@ -474,7 +490,8 @@ export class TelegramAdapter implements ChannelAdapter {
         this._lastError = undefined;
         this._lastErrorAt = undefined;
       },
-    }).catch((error) => {
+    });
+    Promise.resolve(startResult).catch((error) => {
       const description = error instanceof Error ? error.message : String(error);
       this.recordAdapterError(`Telegram connect failed: ${description}`);
       this.scheduleReconnect();
@@ -633,7 +650,7 @@ export class TelegramAdapter implements ChannelAdapter {
 
     this._status = 'connecting';
     await bot.stop();
-    bot.start({
+    const startResult = bot.start({
       onStart: (botInfo) => {
         console.log(`Telegram bot reconnected: @${botInfo.username}`);
         this.botInfo = { id: botInfo.id, username: botInfo.username };
@@ -642,7 +659,8 @@ export class TelegramAdapter implements ChannelAdapter {
         this._lastError = undefined;
         this._lastErrorAt = undefined;
       },
-    }).catch((error) => {
+    });
+    Promise.resolve(startResult).catch((error) => {
       const description = error instanceof Error ? error.message : String(error);
       this.recordAdapterError(`Telegram reconnect polling error: ${description}`);
       this.scheduleReconnect();

src/commands/builtin/index.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect, vi } from 'vitest';
 
-import { createApproveCommand, createApprovalsCommand, createContextCommand, createDenyCommand, createElevateCommand, createModelCommand, createQueueCommand, createResearchCommand, createSkillCommand, createTransferCommand } from './index.js';
+import { createApproveCommand, createApprovalsCommand, createContextCommand, createDenyCommand, createElevateCommand, createModelCommand, createQueueCommand, createResearchCommand, createSkillCommand, createStopCommand, createTransferCommand } from './index.js';
 
 describe('builtin /model command', () => {
   it('passes through the full argument string', async () => {
@@ -198,6 +198,34 @@ describe('builtin /transfer command', () => {
   });
 });
 
+describe('builtin /stop command', () => {
+  it('calls cancelRun service', async () => {
+    const cmd = createStopCommand();
+    const cancelRun = vi.fn(() => 'Cancellation requested.');
+    const result = await cmd.execute([], {
+      channel: 'test',
+      senderId: 'user',
+      sessionId: 's1',
+      rawInput: '/stop',
+      services: { cancelRun },
+    });
+    expect(cancelRun).toHaveBeenCalledOnce();
+    expect(result).toEqual({ handled: true, text: 'Cancellation requested.' });
+  });
+
+  it('returns not-available when service is missing', async () => {
+    const cmd = createStopCommand();
+    const result = await cmd.execute([], {
+      channel: 'test',
+      senderId: 'user',
+      sessionId: 's1',
+      rawInput: '/stop',
+      services: {},
+    });
+    expect(result).toEqual({ handled: true, text: 'Stop command is not available in this session.' });
+  });
+});
+
 describe('builtin approval commands', () => {
   it('calls getApprovals for /approvals', async () => {
     const cmd = createApprovalsCommand();

src/commands/builtin/index.ts

@@ -144,6 +144,23 @@ export function createResetCommand(): CommandDefinition {
   };
 }
 
+export function createStopCommand(): CommandDefinition {
+  return {
+    name: 'stop',
+    aliases: ['cancel'],
+    description: 'Stop the current in-flight run',
+    execute: async (_args, ctx) => {
+      if (!ctx.services?.cancelRun) {
+        return notAvailable('Stop command');
+      }
+      return {
+        handled: true,
+        text: await ctx.services.cancelRun(),
+      };
+    },
+  };
+}
+
 export function createElevateCommand(): CommandDefinition {
   return {
     name: 'elevate',
@@ -309,6 +326,7 @@ export function registerBuiltinCommands(registry: CommandRegistry): void {
   registry.register(createModelCommand());
   registry.register(createCompactCommand());
   registry.register(createResetCommand());
+  registry.register(createStopCommand());
   registry.register(createElevateCommand());
   registry.register(createQueueCommand());
   registry.register(createTransferCommand());

src/commands/index.ts

@@ -8,6 +8,7 @@ export {
   createModelCommand,
   createCompactCommand,
   createResetCommand,
+  createStopCommand,
   createQueueCommand,
   createTransferCommand,
   createApprovalsCommand,

src/commands/types.ts

@@ -34,6 +34,7 @@ export interface CommandServices {
   getQueue?: () => Promise<string> | string;
   setQueue?: (input: string) => Promise<string> | string;
   resetQueue?: () => Promise<string> | string;
+  cancelRun?: () => Promise<string> | string;
   transferSession?: (target: string) => Promise<string> | string;
   getApprovals?: () => Promise<string> | string;
   approvePending?: (input: string) => Promise<string> | string;

src/gateway/handlers/agent.test.ts

@@ -36,6 +36,7 @@ describe('createAgentHandlers command fast-path', () => {
     setBusy: vi.fn(),
     setOnToolUse: vi.fn(),
     isBusy: vi.fn(() => false),
+    cancel: vi.fn(() => true),
   };
 
   const sessionManager = {
@@ -219,6 +220,26 @@ describe('createAgentHandlers command fast-path', () => {
     expect(((sent[0] as GatewayEvent).data as { content: string }).content).toContain('Reset default to: anthropic/claude-sonnet-4');
   });
 
+  it('handles /stop command via fast-path and requests cancellation', async () => {
+    const sent: OutboundMessage[] = [];
+    const send = vi.fn((msg: OutboundMessage) => sent.push(msg));
+    const req: GatewayRequest = {
+      id: 12,
+      method: 'agent.send',
+      params: {
+        message: '/stop',
+        connectionId: 'conn-1',
+        metadata: { isCommand: true, command: 'stop' },
+      },
+    };
+
+    await handlers['agent.send'](req, send);
+
+    expect(sessionBridge.cancel).toHaveBeenCalledWith('conn-1');
+    expect(mockAgent.process).not.toHaveBeenCalled();
+    expect(((sent[0] as GatewayEvent).data as { content: string }).content).toContain('Cancellation requested');
+  });
+
   it('falls through to agent.process for unknown commands', async () => {
     const sent: OutboundMessage[] = [];
     const send = vi.fn((msg: OutboundMessage) => sent.push(msg));

src/gateway/handlers/agent.ts

@@ -294,6 +294,12 @@ export function createAgentHandlers(deps: AgentHandlerDeps) {
                   }
                   return 'Session reset.';
                 },
+                cancelRun: () => {
+                  const cancelled = deps.sessionBridge.cancel(connectionId);
+                  return cancelled
+                    ? 'Cancellation requested. The active operation will stop at the next safe point.'
+                    : 'No active operation to cancel.';
+                },
                 getApprovals: () => {
                   if (!deps.hookEngine) {
                     return 'Approval gates are not enabled in this runtime.';

src/gateway/ui/pages/chat.js

@@ -10,6 +10,7 @@ import { renderSafeMarkdown } from '../lib/markdown.js';
 
 let _currentSession = null;
 let _sending = false;
+let _cancelling = false;
 let _searchMode = false;
 let _slashPopupIndex = -1;
 let _elements = {};
@@ -25,6 +26,8 @@ const SLASH_COMMANDS = [
   { name: '/usage',   desc: 'Show token usage' },
   { name: '/status',  desc: 'Show system health' },
   { name: '/model',   desc: 'Show current model' },
+  { name: '/stop',   desc: 'Stop active response' },
+  { name: '/cancel',   desc: 'Alias for /stop' },
   { name: '/approvals', desc: 'List pending guarded actions' },
   { name: '/approve', desc: 'Approve latest or by id' },
   { name: '/deny', desc: 'Deny latest or by id' },
@@ -462,6 +465,8 @@ function parseSlashCommand(text) {
     case '/usage':   return { type: 'usage' };
     case '/status':  return { type: 'status' };
     case '/model':   return { type: 'model', args };
+    case '/stop': return { type: 'stop' };
+    case '/cancel': return { type: 'cancel' };
     case '/approvals': return { type: 'approvals' };
     case '/approve': return { type: 'approve', args };
     case '/deny': return { type: 'deny', args };
@@ -502,6 +507,8 @@ async function handleSlashCommand(cmd, client) {
         '| `/usage` | Show token usage stats |',
         '| `/status` | Show system health |',
         '| `/model [tier|provider]` | Show or set model tier/provider |',
+        '| `/stop` | Stop active response |',
+        '| `/cancel` | Alias for `/stop` |',
         '| `/approvals` | List pending guarded actions |',
         '| `/approve [id]` | Approve latest pending or specific id |',
         '| `/deny [id] [reason]` | Deny latest pending or specific id |',
@@ -562,6 +569,16 @@ async function handleSlashCommand(cmd, client) {
       }
       return true;
     }
+    case 'stop':
+    case 'cancel': {
+      try {
+        const result = await executeAgentSlashCommand(client, 'stop');
+        showSystemMessage(result || 'Cancellation requested.');
+      } catch (err) {
+        showSystemMessage(`Failed to stop: ${err.message}`);
+      }
+      return true;
+    }
 
     case 'approvals': {
       try {
@@ -680,7 +697,8 @@ async function sendMessage(client, overrideText) {
   }
 
   _sending = true;
-  _elements.sendBtn.disabled = true;
+  _cancelling = false;
+  updateSendButton();
   if (!overrideText && input) {input.value = '';}
 
   // Apply search mode prefix
@@ -750,12 +768,41 @@ async function sendMessage(client, overrideText) {
     placeholder.replaceWith(errorMessage);
   } finally {
     _sending = false;
-    if (_elements.sendBtn) {_elements.sendBtn.disabled = false;}
+    _cancelling = false;
+    updateSendButton();
     clearPendingAttachments();
     scrollToBottom();
   }
 }
 
+function updateSendButton() {
+  if (!_elements.sendBtn) {
+    return;
+  }
+  if (_sending) {
+    _elements.sendBtn.disabled = _cancelling;
+    _elements.sendBtn.textContent = _cancelling ? 'Stopping...' : 'Stop';
+    return;
+  }
+  _elements.sendBtn.disabled = false;
+  _elements.sendBtn.textContent = 'Send';
+}
+
+async function cancelActiveRun(client) {
+  if (!_sending || _cancelling) {
+    return;
+  }
+  _cancelling = true;
+  updateSendButton();
+  try {
+    await client.call('agent.cancel', {});
+  } catch (err) {
+    showSystemMessage(`Cancel failed: ${err.message}`);
+    _cancelling = false;
+    updateSendButton();
+  }
+}
+
 // ── Search SVG Icon ─────────────────────────────────────────
 
 const SEARCH_ICON = '<svg class="w-3.5 h-3.5 fill-current shrink-0" viewBox="0 0 20 20" xmlns="http://www.w3.org/2000/svg"><path d="M8.5 3a5.5 5.5 0 0 1 4.38 8.82l4.15 4.15a.75.75 0 0 1-1.06 1.06l-4.15-4.15A5.5 5.5 0 1 1 8.5 3zm0 1.5a4 4 0 1 0 0 8 4 4 0 0 0 0-8z" fill="currentColor"/></svg>';
@@ -884,7 +931,13 @@ export const ChatPage = {
     });
 
     // Event: send message
-    _elements.sendBtn.addEventListener('click', () => sendMessage(client));
+    _elements.sendBtn.addEventListener('click', () => {
+      if (_sending) {
+        void cancelActiveRun(client);
+        return;
+      }
+      void sendMessage(client);
+    });
 
     // Event: keyboard in textarea
     _elements.input.addEventListener('keydown', (e) => {
@@ -924,7 +977,11 @@ export const ChatPage = {
       if (e.key === 'Enter' && !e.shiftKey) {
         e.preventDefault();
         hideSlashPopup();
-        sendMessage(client);
+        if (_sending) {
+          void cancelActiveRun(client);
+          return;
+        }
+        void sendMessage(client);
       }
     });
 
@@ -950,11 +1007,13 @@ export const ChatPage = {
     if (!_currentSession) {
       _elements.messages.innerHTML = '<div class="text-center py-12 px-6 text-zinc-500 text-sm">Select a session or create a new one to start chatting</div>';
     }
+    updateSendButton();
   },
 
   teardown() {
     _currentSession = null;
     _sending = false;
+    _cancelling = false;
     _searchMode = false;
     _slashPopupIndex = -1;
     _sessionSort = 'recent';