fix: detect receive_id_type dynamically in Feishu adapter

gateway/platforms/feishu.py

@@ -3289,9 +3289,26 @@ async def _send_raw_message(
             content=payload,
             uuid_value=str(uuid.uuid4()),
         )
-        request = self._build_create_message_request("chat_id", body)
+        receive_id_type = self._detect_receive_id_type(chat_id)
+        request = self._build_create_message_request(receive_id_type, body)
         return await asyncio.to_thread(self._client.im.v1.message.create, request)
 
+    @staticmethod
+    def _detect_receive_id_type(receive_id: str) -> str:
+        """Detect the correct receive_id_type based on ID prefix.
+
+        Feishu's im.message.create API requires different receive_id_type values:
+        - User open_id (prefix 'ou_') → 'open_id'
+        - Group chat_id (prefix 'oc_') → 'chat_id'
+        - Union ID (prefix 'on_') → 'union_id'
+        """
+        if receive_id.startswith("ou_"):
+            return "open_id"
+        if receive_id.startswith("on_"):
+            return "union_id"
+        # Default to chat_id for group chats (oc_) and any other format
+        return "chat_id"
+
     @staticmethod
     def _response_succeeded(response: Any) -> bool:
         return bool(response and getattr(response, "success", lambda: False)())

tests/gateway/test_feishu.py

@@ -2855,3 +2855,27 @@ async def _direct(func, *args, **kwargs):
             result = asyncio.run(adapter._resolve_sender_name_from_api("ou_broken"))
 
         self.assertIsNone(result)
+
+
+class TestDetectReceiveIdType(unittest.TestCase):
+    """Regression tests for #9980: receive_id_type detection based on ID prefix."""
+
+    def test_open_id_prefix(self):
+        from gateway.platforms.feishu import FeishuAdapter
+        self.assertEqual(FeishuAdapter._detect_receive_id_type("ou_245ad75b"), "open_id")
+
+    def test_chat_id_prefix(self):
+        from gateway.platforms.feishu import FeishuAdapter
+        self.assertEqual(FeishuAdapter._detect_receive_id_type("oc_1234567890"), "chat_id")
+
+    def test_union_id_prefix(self):
+        from gateway.platforms.feishu import FeishuAdapter
+        self.assertEqual(FeishuAdapter._detect_receive_id_type("on_abcdef"), "union_id")
+
+    def test_unknown_prefix_defaults_to_chat_id(self):
+        from gateway.platforms.feishu import FeishuAdapter
+        self.assertEqual(FeishuAdapter._detect_receive_id_type("some_unknown_id"), "chat_id")
+
+    def test_empty_string_defaults_to_chat_id(self):
+        from gateway.platforms.feishu import FeishuAdapter
+        self.assertEqual(FeishuAdapter._detect_receive_id_type(""), "chat_id")