fix(telegram): stop typing indicator lingering after final reply

After the agent's final response, the '...typing' bubble persisted ~5s.
send() re-triggers send_typing() after every delivery so the bubble
survives intermediate progress messages (Telegram clears typing on each
delivered message). But that re-trigger also fired on the FINAL send,
re-arming Telegram's ~5s timer AFTER the gateway had already torn down
its typing-refresh loop — and Telegram exposes no stop-typing API, so
nothing cancelled it.

Gate the post-send re-trigger on the absence of metadata['notify'] (set
only on the final user-visible reply via _mark_notify_metadata). Both
the rich-message and legacy send paths are covered; intermediate
progress sends still re-trigger so the bubble stays alive mid-response.

Fixes #48678

plugins/platforms/telegram/adapter.py

@@ -2517,11 +2517,17 @@ class TelegramAdapter(BasePlatformAdapter):
                 rich_result = await self._try_send_rich(chat_id, content, reply_to, metadata)
                 if rich_result is not None:
                     if rich_result.success:
-                        # Re-trigger typing like the legacy success path does.
-                        try:
-                            await self.send_typing(chat_id, metadata=metadata)
-                        except Exception:
-                            pass  # Typing failures are non-fatal
+                        # Re-trigger typing like the legacy success path does,
+                        # but ONLY for intermediate sends. On the final reply
+                        # (metadata["notify"]) the gateway has already torn down
+                        # the typing refresh loop; re-arming Telegram's ~5s timer
+                        # here would leave the "...typing" bubble lingering after
+                        # the answer (no Bot API call cancels it). See #48678.
+                        if not (metadata or {}).get("notify"):
+                            try:
+                                await self.send_typing(chat_id, metadata=metadata)
+                            except Exception:
+                                pass  # Typing failures are non-fatal
                     return rich_result
 
             # Format and split message if needed
@@ -2746,10 +2752,16 @@ class TelegramAdapter(BasePlatformAdapter):
             # so without this the "...typing" bubble disappears mid-response
             # (especially noticeable when the agent sends intermediate progress
             # messages like "Checking:" before running tools).
-            try:
-                await self.send_typing(chat_id, metadata=metadata)
-            except Exception:
-                pass  # Typing failures are non-fatal
+            # Skip this on the FINAL reply (metadata["notify"]): the gateway has
+            # already cancelled the typing refresh loop by the time the final
+            # send returns, so re-arming Telegram's ~5s timer here would leave
+            # the indicator lingering after the answer with nothing to cancel
+            # it (Telegram exposes no stop-typing API). See #48678.
+            if not (metadata or {}).get("notify"):
+                try:
+                    await self.send_typing(chat_id, metadata=metadata)
+                except Exception:
+                    pass  # Typing failures are non-fatal
 
             return SendResult(
                 success=True,

tests/gateway/test_telegram_format.py

@@ -213,6 +213,39 @@ async def test_legacy_send_keeps_chunk_indicators_outside_fenced_code_lines(adap
             assert not re.match(r"^```\s+\(\d+/\d+\)$", line), text
 
 
+@pytest.mark.asyncio
+async def test_final_send_does_not_retrigger_typing(adapter):
+    """The final reply (metadata['notify']) must NOT re-arm Telegram's typing
+    timer. The gateway has already torn down the refresh loop by then, so a
+    re-trigger here would leave the '...typing' bubble lingering after the
+    answer (Telegram has no stop-typing API). See #48678."""
+    adapter._bot = MagicMock()
+    adapter._bot.send_message = AsyncMock(return_value=SimpleNamespace(message_id=1))
+    adapter._bot.send_chat_action = AsyncMock()
+    adapter._rich_messages_enabled = False
+
+    result = await adapter.send("12345", "All done.", metadata={"notify": True})
+
+    assert result.success is True
+    adapter._bot.send_chat_action.assert_not_called()
+
+
+@pytest.mark.asyncio
+async def test_intermediate_send_still_retriggers_typing(adapter):
+    """Intermediate/progress sends (no notify marker) keep re-triggering typing
+    so the '...typing' bubble survives across progress messages while the agent
+    is still working."""
+    adapter._bot = MagicMock()
+    adapter._bot.send_message = AsyncMock(return_value=SimpleNamespace(message_id=1))
+    adapter._bot.send_chat_action = AsyncMock()
+    adapter._rich_messages_enabled = False
+
+    result = await adapter.send("12345", "Checking:", metadata={"expect_edits": True})
+
+    assert result.success is True
+    adapter._bot.send_chat_action.assert_awaited()
+
+
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