diff --git a/pipeline_service/agent_loop_v2.py b/pipeline_service/agent_loop_v2.py
index 4221a94..d7bc2e9 100644
--- a/pipeline_service/agent_loop_v2.py
+++ b/pipeline_service/agent_loop_v2.py
@@ -128,6 +128,14 @@ class AgentExecutor:
             # 5b. LLM 调用
             raw = await self._call_llm()
 
+            # debug: show raw LLM output
+            yield json.dumps({
+                "type": "debug_raw",
+                "turn": self._turn_count,
+                "raw_len": len(raw) if raw else 0,
+                "raw_preview": (raw or "")[:200],
+            }, ensure_ascii=False) + "\n"
+
             # 5c. 解析 LLM 输出
             actions = self._parse_actions(raw)