diff --git a/core/orchestrator.py b/core/orchestrator.py
index 952fad3..dcce2ae 100644
--- a/core/orchestrator.py
+++ b/core/orchestrator.py
@@ -26,6 +26,7 @@ logger = logging.getLogger("cs_agent")
 MSG_DEDUP_CAPACITY = 200          # 消息 ID 去重缓存容量
 TRANSFER_COOLDOWN_SEC = 120       # 转接冷却时间（秒）—— 转接后2分钟内不再调用AI
 DEBOUNCE_SECONDS = 2.0            # 消息防抖延迟（秒）
+FIRST_GREETING_IDLE_SEC = 180     # 超过该空闲时间，视为新一轮对话
 PENDING_TRANSFER_POLL_SECONDS = 30
 PENDING_TRANSFER_RETRY_SECONDS = 60
 TRANSFER_RETRY_WINDOW_SEC = 300
@@ -86,6 +87,7 @@ class SystemOrchestrator:
         self._debounce_tasks: Dict[str, asyncio.Task] = {}
         self._pending_messages: Dict[str, List[StandardMessage]] = {}
         self._user_locks: Dict[str, asyncio.Lock] = {}
+        self._last_inbound_seen_time: Dict[str, float] = {}
         self._pending_transfer_task: Optional[asyncio.Task] = None
         self._last_retry_transfer_time: Dict[str, float] = {}
         self._auto_pipeline_jobs: Dict[str, float] = {}
@@ -415,20 +417,24 @@ class SystemOrchestrator:
                 if std_msg.msg_id in self._processed_msg_ids: return
                 self._processed_msg_ids.append(std_msg.msg_id)
 
-            # 每次收到客户新消息：先立即回一条固定承接，不经过 AI
-            first_greet = StandardResponse(
-                reply_content="在的 亲",
-                metadata={"acc_id": std_msg.acc_id, "acc_type": std_msg.acc_type},
-            )
-            await self.qianniu_adapter.translate_outbound(first_greet, user_id)
-            await repo.save_chat(
-                platform,
-                user_id,
-                first_greet.reply_content,
-                "out",
-                acc_id=std_msg.acc_id,
-                msg_type=first_greet.msg_type,
-            )
+            # 同一轮对话只在第一句先发固定承接，不经过 AI
+            now_ts = time.time()
+            last_inbound_ts = self._last_inbound_seen_time.get(session_key, 0.0)
+            self._last_inbound_seen_time[session_key] = now_ts
+            if now_ts - last_inbound_ts >= FIRST_GREETING_IDLE_SEC:
+                first_greet = StandardResponse(
+                    reply_content="在的 亲",
+                    metadata={"acc_id": std_msg.acc_id, "acc_type": std_msg.acc_type},
+                )
+                await self.qianniu_adapter.translate_outbound(first_greet, user_id)
+                await repo.save_chat(
+                    platform,
+                    user_id,
+                    first_greet.reply_content,
+                    "out",
+                    acc_id=std_msg.acc_id,
+                    msg_type=first_greet.msg_type,
+                )
 
             # 进入防抖（使用 session_key 隔离不同店铺） 
             if session_key in self._debounce_tasks: self._debounce_tasks[session_key].cancel()