diff --git a/nanobot/channels/feishu.py b/nanobot/channels/feishu.py
index 56e6df1c3..6f3503236 100644
--- a/nanobot/channels/feishu.py
+++ b/nanobot/channels/feishu.py
@@ -308,6 +308,8 @@ class FeishuChannel(BaseChannel):
         self._loop: asyncio.AbstractEventLoop | None = None
         self._stream_bufs: dict[str, _FeishuStreamBuf] = {}
         self._bot_open_id: str | None = None
+        self._background_tasks: set[asyncio.Task] = set()
+        self._reaction_ids: dict[str, str] = {}  # message_id → reaction_id
 
     @staticmethod
     def _register_optional_event(builder: Any, method_name: str, handler: Any) -> Any:
@@ -549,8 +551,11 @@ class FeishuChannel(BaseChannel):
             return None
 
     async def _add_reaction(self, message_id: str, emoji_type: str = "THUMBSUP") -> str | None:
-        """
-        Add a reaction emoji to a message (non-blocking).
+        """Add a reaction emoji to a message.
+
+        Returns the reaction_id on success, None on failure.
+        When called via a tracked background task, the returned reaction_id
+        is stored in ``_reaction_ids`` for later cleanup by ``send_delta``.
 
         Common emoji types: THUMBSUP, OK, EYES, DONE, OnIt, HEART
         """
@@ -594,6 +599,30 @@ class FeishuChannel(BaseChannel):
         loop = asyncio.get_running_loop()
         await loop.run_in_executor(None, self._remove_reaction_sync, message_id, reaction_id)
 
+    def _on_background_task_done(self, task: asyncio.Task) -> None:
+        """Callback: remove from tracking set and log unhandled exceptions."""
+        self._background_tasks.discard(task)
+        if task.cancelled():
+            return
+        try:
+            task.result()
+        except Exception as exc:
+            logger.warning("Background task failed: {}", exc)
+
+    def _on_reaction_added(self, message_id: str, task: asyncio.Task) -> None:
+        """Callback: store reaction_id after background add-reaction completes."""
+        if task.cancelled():
+            return
+        try:
+            reaction_id = task.result()
+            if reaction_id:
+                self._reaction_ids[message_id] = reaction_id
+        except Exception:
+            pass  # already logged by _on_background_task_done
+        # Trim cache to prevent unbounded growth
+        if len(self._reaction_ids) > 500:
+            self._reaction_ids.pop(next(iter(self._reaction_ids)))
+
     # Regex to match markdown tables (header + separator + data rows)
     _TABLE_RE = re.compile(
         r"((?:^[ \t]*\|.+\|[ \t]*\n)(?:^[ \t]*\|[-:\s|]+\|[ \t]*\n)(?:^[ \t]*\|.+\|[ \t]*\n?)+)",
@@ -1172,8 +1201,19 @@ class FeishuChannel(BaseChannel):
             logger.error("Error sending Feishu {} message: {}", msg_type, e)
             return None
 
-    def _create_streaming_card_sync(self, receive_id_type: str, chat_id: str) -> str | None:
-        """Create a CardKit streaming card, send it to chat, return card_id."""
+    def _create_streaming_card_sync(
+        self,
+        receive_id_type: str,
+        chat_id: str,
+        reply_message_id: str | None = None,
+    ) -> str | None:
+        """Create a CardKit streaming card, send it to chat, return card_id.
+
+        When *reply_message_id* is provided the card is delivered via the
+        reply API (with reply_in_thread=True) so it lands inside the
+        originating thread / topic.  Otherwise the plain create-message
+        API is used.
+        """
         from lark_oapi.api.cardkit.v1 import CreateCardRequest, CreateCardRequestBody
 
         card_json = {
@@ -1202,13 +1242,19 @@ class FeishuChannel(BaseChannel):
                 return None
             card_id = getattr(response.data, "card_id", None)
             if card_id:
-                message_id = self._send_message_sync(
-                    receive_id_type,
-                    chat_id,
-                    "interactive",
-                    json.dumps({"type": "card", "data": {"card_id": card_id}}),
+                card_content = json.dumps(
+                    {"type": "card", "data": {"card_id": card_id}}, ensure_ascii=False
                 )
-                if message_id:
+                if reply_message_id:
+                    sent = self._reply_message_sync(
+                        reply_message_id, "interactive", card_content,
+                        reply_in_thread=True,
+                    )
+                else:
+                    sent = self._send_message_sync(
+                        receive_id_type, chat_id, "interactive", card_content,
+                    ) is not None
+                if sent:
                     return card_id
                 logger.warning(
                     "Created streaming card {} but failed to send it to {}", card_id, chat_id
@@ -1298,7 +1344,7 @@ class FeishuChannel(BaseChannel):
             _stream_end: Finalize the streaming card.
             _tool_hint:  Delta is a formatted tool hint (for display only).
             message_id:  Original message id (used with _stream_end for reaction cleanup).
-            reaction_id: Reaction id to remove on stream end.
+            chat_type:   "group" or "p2p" — controls reply-in-thread for streaming cards.
         """
         if not self._client:
             return
@@ -1308,10 +1354,13 @@ class FeishuChannel(BaseChannel):
 
         # --- stream end: final update or fallback ---
         if meta.get("_stream_end"):
-            if (message_id := meta.get("message_id")) and (reaction_id := meta.get("reaction_id")):
-                await self._remove_reaction(message_id, reaction_id)
+            message_id = meta.get("message_id")
+            if message_id:
+                reaction_id = self._reaction_ids.pop(message_id, None)
+                if reaction_id:
+                    await self._remove_reaction(message_id, reaction_id)
                 # Add completion emoji if configured
-                if self.config.done_emoji and message_id:
+                if self.config.done_emoji:
                     await self._add_reaction(message_id, self.config.done_emoji)
 
             buf = self._stream_bufs.pop(chat_id, None)
@@ -1349,9 +1398,22 @@ class FeishuChannel(BaseChannel):
                     {"config": {"wide_screen_mode": True}, "elements": chunk},
                     ensure_ascii=False,
                 )
-                await loop.run_in_executor(
-                    None, self._send_message_sync, rid_type, chat_id, "interactive", card
-                )
+                # Fallback: reply via the Reply API for group chats.
+                # Target message_id — the Feishu API keeps the reply in
+                # the same topic automatically.
+                _f_msg = meta.get("message_id")
+                fallback_msg_id = _f_msg if meta.get("chat_type", "group") == "group" else None
+                if fallback_msg_id:
+                    await loop.run_in_executor(
+                        None, lambda: self._reply_message_sync(
+                            fallback_msg_id, "interactive", card,
+                            reply_in_thread=True,
+                        ),
+                    )
+                else:
+                    await loop.run_in_executor(
+                        None, self._send_message_sync, rid_type, chat_id, "interactive", card
+                    )
             return
 
         # --- accumulate delta ---
@@ -1365,8 +1427,16 @@ class FeishuChannel(BaseChannel):
 
         now = time.monotonic()
         if buf.card_id is None:
+            # Send the streaming card as a reply for group chats so it
+            # lands inside the originating topic/thread.  Always target
+            # message_id (the actual inbound message) — the Feishu Reply
+            # API keeps the response in the same topic automatically.
+            is_group = meta.get("chat_type", "group") == "group"
+            reply_msg_id = meta.get("message_id") if is_group else None
             card_id = await loop.run_in_executor(
-                None, self._create_streaming_card_sync, rid_type, chat_id
+                None,
+                self._create_streaming_card_sync,
+                rid_type, chat_id, reply_msg_id,
             )
             if card_id:
                 buf.card_id = card_id
@@ -1410,43 +1480,58 @@ class FeishuChannel(BaseChannel):
                     return
                 # No active streaming card — send as a regular
                 # interactive card with the same 🔧 prefix style.
+                # Use reply API for group chats so the hint stays in topic.
                 card = json.dumps(
                     {"config": {"wide_screen_mode": True}, "elements": [
                         {"tag": "markdown", "content": self._format_tool_hint_delta(hint)},
                     ]},
                     ensure_ascii=False,
                 )
-                await loop.run_in_executor(
-                    None, self._send_message_sync, receive_id_type, msg.chat_id, "interactive", card
-                )
+                _th_msg_id = msg.metadata.get("message_id")
+                _th_chat_type = msg.metadata.get("chat_type", "group")
+                if _th_msg_id and _th_chat_type == "group":
+                    await loop.run_in_executor(
+                        None, lambda: self._reply_message_sync(
+                            _th_msg_id, "interactive", card,
+                            reply_in_thread=True,
+                        ),
+                    )
+                else:
+                    await loop.run_in_executor(
+                        None, self._send_message_sync, receive_id_type, msg.chat_id, "interactive", card
+                    )
                 return
 
             # Determine whether the first message should quote the user's message.
             # Only the very first send (media or text) in this call uses reply; subsequent
             # chunks/media fall back to plain create to avoid redundant quote bubbles.
+            # Always target message_id — the Feishu Reply API keeps replies in the
+            # same topic automatically when the target message is inside a topic.
             reply_message_id: str | None = None
+            _msg_id = msg.metadata.get("message_id")
             if self.config.reply_to_message and not msg.metadata.get("_progress", False):
-                reply_message_id = msg.metadata.get("message_id") or None
+                reply_message_id = _msg_id
             # For topic group messages, always reply to keep context in thread
             elif msg.metadata.get("thread_id"):
-                reply_message_id = (
-                    msg.metadata.get("root_id") or msg.metadata.get("message_id") or None
-                )
+                reply_message_id = _msg_id
 
             first_send = True  # tracks whether the reply has already been used
 
             def _do_send(m_type: str, content: str) -> None:
                 """Send via reply (first message) or create (subsequent).
 
-                When reply_to_message is enabled, the first message uses
-                reply_in_thread=True to create a visual topic thread.
+                For group chats the reply API always uses reply_in_thread=True.
+                The Feishu API automatically keeps replies inside existing
+                topics — reply_in_thread only creates a *new* topic when the
+                target message is a plain (non-topic) message.
                 """
                 nonlocal first_send
                 if reply_message_id and first_send:
                     first_send = False
+                    chat_type = msg.metadata.get("chat_type", "group")
                     ok = self._reply_message_sync(
                         reply_message_id, m_type, content,
-                        reply_in_thread=self.config.reply_to_message,
+                        reply_in_thread=chat_type == "group",
                     )
                     if ok:
                         return
@@ -1556,9 +1641,13 @@ class FeishuChannel(BaseChannel):
                 logger.debug("Feishu: skipping group message (not mentioned)")
                 return
 
-            # Add reaction (non-blocking — fire and forget)
-            reaction_id = None
-            asyncio.create_task(self._add_reaction(message_id, self.config.react_emoji))
+            # Add reaction (non-blocking — tracked background task)
+            task = asyncio.create_task(
+                self._add_reaction(message_id, self.config.react_emoji)
+            )
+            self._background_tasks.add(task)
+            task.add_done_callback(self._on_background_task_done)
+            task.add_done_callback(lambda t: self._on_reaction_added(message_id, t))
 
             # Parse content
             content_parts = []
@@ -1656,7 +1745,6 @@ class FeishuChannel(BaseChannel):
                 media=media_paths,
                 metadata={
                     "message_id": message_id,
-                    "reaction_id": reaction_id,
                     "chat_type": chat_type,
                     "msg_type": msg_type,
                     "parent_id": parent_id,
diff --git a/tests/channels/test_feishu_reply.py b/tests/channels/test_feishu_reply.py
index f40ffabc9..c09d4ae55 100644
--- a/tests/channels/test_feishu_reply.py
+++ b/tests/channels/test_feishu_reply.py
@@ -606,3 +606,127 @@ async def test_reply_keeps_fallback_when_reply_fails() -> None:
 
     channel._client.im.v1.message.reply.assert_called()
     channel._client.im.v1.message.create.assert_called()
+
+
+@pytest.mark.asyncio
+async def test_reply_no_reply_in_thread_for_p2p_chat() -> None:
+    """reply_in_thread should NOT be set for p2p chats (identified by chat_type)."""
+    channel = _make_feishu_channel(reply_to_message=True)
+
+    reply_resp = MagicMock()
+    reply_resp.success.return_value = True
+    channel._client.im.v1.message.reply.return_value = reply_resp
+
+    await channel.send(OutboundMessage(
+        channel="feishu",
+        chat_id="oc_abc",  # p2p chats also use oc_ prefix
+        content="hello",
+        metadata={"message_id": "om_001", "chat_type": "p2p"},
+    ))
+
+    channel._client.im.v1.message.reply.assert_called_once()
+    call_args = channel._client.im.v1.message.reply.call_args
+    request = call_args[0][0]
+    assert request.request_body.reply_in_thread is not True
+
+
+@pytest.mark.asyncio
+async def test_reply_uses_reply_in_thread_for_group_chat() -> None:
+    """reply_in_thread should be True for group chats (identified by chat_type)."""
+    channel = _make_feishu_channel(reply_to_message=True)
+
+    reply_resp = MagicMock()
+    reply_resp.success.return_value = True
+    channel._client.im.v1.message.reply.return_value = reply_resp
+
+    await channel.send(OutboundMessage(
+        channel="feishu",
+        chat_id="oc_abc",
+        content="hello",
+        metadata={"message_id": "om_001", "chat_type": "group"},
+    ))
+
+    channel._client.im.v1.message.reply.assert_called_once()
+    call_args = channel._client.im.v1.message.reply.call_args
+    request = call_args[0][0]
+    assert request.request_body.reply_in_thread is True
+
+
+@pytest.mark.asyncio
+async def test_reply_targets_message_id_when_in_topic() -> None:
+    """When inbound message is inside a topic (root_id != message_id),
+    the reply should target the inbound message_id (not root_id).
+    The Feishu Reply API keeps the response in the same topic
+    automatically when the target message is already inside a topic."""
+    channel = _make_feishu_channel(reply_to_message=True)
+
+    reply_resp = MagicMock()
+    reply_resp.success.return_value = True
+    channel._client.im.v1.message.reply.return_value = reply_resp
+
+    await channel.send(OutboundMessage(
+        channel="feishu",
+        chat_id="oc_abc",
+        content="hello",
+        metadata={
+            "message_id": "om_child456",
+            "chat_type": "group",
+            "root_id": "om_root123",
+        },
+    ))
+
+    channel._client.im.v1.message.reply.assert_called_once()
+    call_args = channel._client.im.v1.message.reply.call_args
+    request = call_args[0][0]
+    # Should reply to the inbound message_id, not the root
+    assert request.message_id == "om_child456"
+    assert request.request_body.reply_in_thread is True
+
+
+def test_on_reaction_added_stores_reaction_id() -> None:
+    """_on_reaction_added stores the returned reaction_id in _reaction_ids."""
+    channel = _make_feishu_channel()
+    loop = asyncio.new_event_loop()
+    try:
+        task = loop.create_task(asyncio.sleep(0, result="reaction_abc"))
+        loop.run_until_complete(task)
+        channel._on_reaction_added("om_001", task)
+    finally:
+        loop.close()
+
+    assert channel._reaction_ids["om_001"] == "reaction_abc"
+
+
+def test_on_reaction_added_skips_none_result() -> None:
+    """_on_reaction_added does not store None results."""
+    channel = _make_feishu_channel()
+    loop = asyncio.new_event_loop()
+    try:
+        task = loop.create_task(asyncio.sleep(0, result=None))
+        loop.run_until_complete(task)
+        channel._on_reaction_added("om_001", task)
+    finally:
+        loop.close()
+
+    assert "om_001" not in channel._reaction_ids
+
+
+def test_on_background_task_done_removes_from_set() -> None:
+    """_on_background_task_done removes task from tracking set."""
+    channel = _make_feishu_channel()
+    loop = asyncio.new_event_loop()
+    try:
+        async def _fail():
+            raise RuntimeError("test failure")
+
+        task = loop.create_task(_fail())
+        channel._background_tasks.add(task)
+        try:
+            loop.run_until_complete(task)
+        except RuntimeError:
+            pass  # expected
+        channel._on_background_task_done(task)
+    finally:
+        loop.close()
+
+    assert task not in channel._background_tasks