fix: restore implicit follow-up continuation

src/message-runtime.test.ts

@@ -314,6 +314,99 @@ describe('createMessageRuntime', () => {
     expect(saveState).toHaveBeenCalled();
   });
 
+  it('allows follow-up messages without a trigger after a visible reply in non-main groups', async () => {
+    const chatJid = 'group@test';
+    const group: RegisteredGroup = {
+      ...makeGroup('codex'),
+      requiresTrigger: true,
+    };
+    const channel = makeChannel(chatJid);
+    const saveState = vi.fn();
+    const lastAgentTimestamps: Record<string, string> = {};
+
+    vi.mocked(db.getMessagesSince)
+      .mockReturnValueOnce([
+        {
+          id: 'msg-1',
+          chat_jid: chatJid,
+          sender: 'user@test',
+          sender_name: 'User',
+          content: '@Andy 첫 요청',
+          timestamp: '2026-03-18T09:00:00.000Z',
+        },
+      ])
+      .mockReturnValueOnce([
+        {
+          id: 'msg-2',
+          chat_jid: chatJid,
+          sender: 'user@test',
+          sender_name: 'User',
+          content: '두 번째 말은 멘션 없이 이어서',
+          timestamp: '2026-03-18T09:00:10.000Z',
+        },
+      ]);
+
+    vi.mocked(agentRunner.runAgentProcess).mockImplementation(
+      async (_group, _input, _onProcess, onOutput) => {
+        await onOutput?.({
+          status: 'success',
+          result: '응답했습니다.',
+          phase: 'final',
+        });
+        return {
+          status: 'success',
+          result: '응답했습니다.',
+          phase: 'final',
+        };
+      },
+    );
+
+    const runtime = createMessageRuntime({
+      assistantName: 'Andy',
+      idleTimeout: 60_000,
+      pollInterval: 1_000,
+      timezone: 'UTC',
+      triggerPattern: /^@Andy\b/i,
+      channels: [channel],
+      queue: {
+        registerProcess: vi.fn(),
+        closeStdin: vi.fn(),
+        notifyIdle: vi.fn(),
+      } as any,
+      getRegisteredGroups: () => ({ [chatJid]: group }),
+      getSessions: () => ({}),
+      getLastTimestamp: () => '',
+      setLastTimestamp: vi.fn(),
+      getLastAgentTimestamps: () => lastAgentTimestamps,
+      saveState,
+      persistSession: vi.fn(),
+      clearSession: vi.fn(),
+    });
+
+    const first = await runtime.processGroupMessages(chatJid, {
+      runId: 'run-triggered-first-turn',
+      reason: 'messages',
+    });
+    const second = await runtime.processGroupMessages(chatJid, {
+      runId: 'run-triggerless-follow-up',
+      reason: 'messages',
+    });
+
+    expect(first).toBe(true);
+    expect(second).toBe(true);
+    expect(agentRunner.runAgentProcess).toHaveBeenCalledTimes(2);
+    expect(channel.sendMessage).toHaveBeenNthCalledWith(
+      1,
+      chatJid,
+      '응답했습니다.',
+    );
+    expect(channel.sendMessage).toHaveBeenNthCalledWith(
+      2,
+      chatJid,
+      '응답했습니다.',
+    );
+  });
+
   it('clears Claude sessions and closes stdin immediately on poisoned output', async () => {
     const chatJid = 'group@test';
     const group = makeGroup('claude-code');

src/message-runtime.ts

@@ -86,6 +86,7 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
   startMessageLoop: () => Promise<void>;
 } {
   let messageLoopRunning = false;
+  const implicitContinuationUntil = new Map<string, number>();
 
   const getCurrentAvailableGroups = (): AvailableGroup[] =>
     getAvailableGroups(deps.getRegisteredGroups());
@@ -115,6 +116,24 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
     deps.saveState();
   };
 
+  const openImplicitContinuationWindow = (chatJid: string): void => {
+    if (deps.idleTimeout <= 0) return;
+    implicitContinuationUntil.set(chatJid, Date.now() + deps.idleTimeout);
+  };
+
+  const hasImplicitContinuationWindow = (
+    chatJid: string,
+    messages: NewMessage[],
+  ): boolean => {
+    const until = implicitContinuationUntil.get(chatJid);
+    if (!until) return false;
+    if (Date.now() > until) {
+      implicitContinuationUntil.delete(chatJid);
+      return false;
+    }
+    return messages.some((message) => message.is_from_me !== true);
+  };
+
   const getProcessableMessages = (
     chatJid: string,
     messages: Parameters<typeof filterProcessableMessages>[0],
@@ -138,10 +157,7 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
     // into a reply loop.
     return messages.filter(
       (message) =>
-        !(
-          message.is_bot_message &&
-          message.content.trim() === failureText
-        ),
+        !(message.is_bot_message && message.content.trim() === failureText),
     );
   };
 
@@ -161,6 +177,7 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
           item.result_payload,
         );
         markWorkItemDelivered(item.id, replaceMessageId);
+        openImplicitContinuationWindow(item.chat_jid);
         logger.info(
           {
             chatJid: item.chat_jid,
@@ -188,6 +205,7 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
     try {
       await channel.sendMessage(item.chat_jid, item.result_payload);
       markWorkItemDelivered(item.id);
+      openImplicitContinuationWindow(item.chat_jid);
       logger.info(
         {
           chatJid: item.chat_jid,
@@ -655,7 +673,10 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
             (msg.is_from_me ||
               isTriggerAllowed(chatJid, msg.sender, allowlistCfg)),
         );
-        if (!hasTrigger) {
+        if (
+          !hasTrigger &&
+          !hasImplicitContinuationWindow(chatJid, missedMessages)
+        ) {
           logger.info(
             { chatJid, group: group.name, groupFolder: group.folder, runId },
             'Skipping queued run because no allowed trigger was found',
@@ -1203,7 +1224,12 @@ export function createMessageRuntime(deps: MessageRuntimeDeps): {
                   (msg.is_from_me ||
                     isTriggerAllowed(chatJid, msg.sender, allowlistCfg)),
               );
-              if (!hasTrigger) continue;
+              if (
+                !hasTrigger &&
+                !hasImplicitContinuationWindow(chatJid, processableGroupMessages)
+              ) {
+                continue;
+              }
             }
 
             deps.queue.enqueueMessageCheck(chatJid, group.folder);