feat(langfuse): 목록 한 줄 = 채팅(질문/답/토큰), 트리 = OpenCode 도구 호출(SAP 조회·위키 read·grep) 순서대로

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

5_django_backend/apps/chat/stream.py

@@ -192,6 +192,21 @@ class TurnState:
         return out
 
 
+def _tool_spans(tid: str, root: dict, tool_parts: list[dict]) -> list[dict]:
+    """OpenCode 도구 파트 → Langfuse 자식 span. 출력은 앞 4KB 만(원문은 OpenCode 에 있음)."""
+    out = []
+    for p in tool_parts:
+        st = p.get("state") or {}
+        t = st.get("time") or {}
+        out.append(langfuse.tool_span(
+            tid, p.get("tool") or "tool", parent=root, input=st.get("input"), title=st.get("title") or "",
+            output=(st.get("output") or "")[:4000] or None,
+            start=langfuse.ms_iso(t.get("start")), end=langfuse.ms_iso(t.get("end")),
+            error=st.get("error") if st.get("status") == "error" else None,
+        ))
+    return out
+
+
 def _real_title(raw) -> str | None:
     """OpenCode 기본 제목("New session - 2026-…")은 제목이 아님 → None."""
     t = (raw or "").strip()
@@ -212,12 +227,15 @@ async def _finalize(session: ChatSession, state: TurnState, started: float, *, f
     content = state.accumulated()
     usage: dict | None = None
     title = state.title
+    tool_parts: list[dict] = []
     try:
         msgs = await opencode_service.list_messages_a(session.id) or []
         assistant = [m for m in msgs if (m.get("info") or {}).get("role") == "assistant"]
         if assistant:
             info = assistant[-1]["info"]
             parts = assistant[-1].get("parts") or []
+            # 이 턴의 assistant 메시지가 여러 개(도구 왕복마다 하나)라 도구 파트는 전부 모음
+            tool_parts = [p for m in assistant for p in (m.get("parts") or []) if p.get("type") == "tool"]
             full = "".join(p.get("text", "") for p in parts if p.get("type") == "text" and not p.get("synthetic"))
             if full:
                 content = full
@@ -251,25 +269,18 @@ async def _finalize(session: ChatSession, state: TurnState, started: float, *, f
         session.title_llm = title[:200]
     await session.asave(update_fields=["is_generating", "title_llm", "updated_at"])
 
-    # 관측: 사용자 단위 trace 하나 + 답변 generation 하나. 실패해도 여기까진 이미 저장됨.
+    # 관측: 목록 한 줄 = 이 채팅(질문·답·토큰). 트리 = 답 만들며 부른 도구들(SAP 조회·위키 read…) 순서대로.
     if langfuse.enabled():
         tid = f"{session.id}-{int(started * 1000)}"
         user_email = await sync_to_async(lambda: session.user.email)()
-        meta = {"failed": failed} if failed else {}
         t0 = datetime.fromtimestamp(started, timezone.utc).isoformat()
-        root = langfuse.trace(tid, "chat", userId=user_email, sessionId=session.id, input=state.user_text,
-                              output=content, metadata=meta, tags=["codeassist"], start=t0, end=langfuse.now_iso())
-        langfuse.send_later([
-            root,
-            langfuse.generation(
-                tid, "opencode-turn", parent=root,
-                startTime=t0, endTime=langfuse.now_iso(),
-                input=state.user_text, output=content,
-                usage=langfuse.usage_of(usage["input"], usage["output"]) if usage else None,
-                level="ERROR" if failed else "DEFAULT", statusMessage=failed or "",
-                metadata={"elapsed_ms": usage["elapsed_ms"]} if usage else {},
-            ),
-        ])
+        root = langfuse.trace(
+            tid, "chat", userId=user_email, sessionId=session.id, input=state.user_text, output=content,
+            tags=["codeassist"], start=t0, end=langfuse.now_iso(),
+            usage=langfuse.usage_of(usage["input"], usage["output"]) if usage else None,
+            metadata={"elapsed_ms": usage["elapsed_ms"]} if usage else {}, error=failed,
+        )
+        langfuse.send_later([root, *_tool_spans(tid, root, tool_parts)])
     return usage, title