fix(assistant): 流式 tool_calls 缺 id 时补一次并复用, tool 回填的 tool_call_id 与助手消息一致

部分 OpenAI 兼容网关的流式 tool_calls 分片不带 id。chat_stream 构造助手消息时
用 uuid 兜底了 tool_calls[].id, 但这个值是在列表推导里现场生成的, 没有写回 call;
紧接着的 role:tool 回填取的是 call.get("id") or "", 于是 tool_call_id 为空串,
与助手消息对不上, 严格校验协议的上游会拒绝下一轮请求。

构造助手消息前给缺 id 的 call 生成一次 id 并写回, 助手消息与回填统一用 call["id"]。
上游自带 id 时不变。

Closes #351

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

backend/app/custom/assistant/chat_service.py

@@ -220,11 +220,17 @@ async def chat_stream(
                     ))
                     return
 
+                # 部分兼容网关的流式 tool_calls 不带 id: 补一次并写回 call, 助手消息的
+                # tool_calls[].id 与下方 role:tool 回填的 tool_call_id 必须是同一个值。
+                for call in tool_calls:
+                    if not call.get("id"):
+                        call["id"] = uuid.uuid4().hex[:8]
+
                 assistant_message: dict[str, Any] = {
                     "role": "assistant",
                     "tool_calls": [
                         {
-                            "id": call.get("id") or uuid.uuid4().hex[:8],
+                            "id": call["id"],
                             "type": "function",
                             "function": {"name": call.get("name", ""), "arguments": call.get("arguments", "")},
                         }
@@ -243,7 +249,7 @@ async def chat_stream(
                     )
                     req_messages.append({
                         "role": "tool",
-                        "tool_call_id": call.get("id") or "",
+                        "tool_call_id": call["id"],
                         "content": json.dumps(result, ensure_ascii=False),
                     })
         except Exception as exc:  # 单轮失败收敛为 error 事件, 不打断流

backend/tests/test_assistant_tool_call_id.py

@@ -0,0 +1,86 @@
+"""AI 助手工具轮次: 流式 tool_calls 缺 id 时, 回填消息的 tool_call_id 必须与助手消息一致。
+
+部分 OpenAI 兼容网关的流式 tool_calls 分片不带 id (streaming 累积后 id 为空串)。
+chat_service 给助手消息的 tool_calls[].id 补了随机 id, 但 role:tool 回填消息的
+tool_call_id 仍取原始空串 —— 两者对不上, 下一轮请求会被上游按协议拒绝
+(tool 消息找不到对应的 tool_call), 对话在第一次取数后直接失败。
+"""
+from __future__ import annotations
+
+import json
+from typing import Any
+
+import pytest
+
+from app.custom.assistant import chat_service
+from app.custom.assistant import tools as assistant_tools
+
+
+def _script_round(script: list[dict[str, Any]], capture: list[list[dict[str, Any]]]):
+    async def fake_round(messages, tool_schemas, *, temperature=0.3, timeout=240.0):
+        capture.append([dict(m) for m in messages])
+        step = script.pop(0)
+        for piece in step.get("text_pieces", []):
+            yield {"type": "text", "delta": piece}
+        yield {"type": "round_end", "tool_calls": step.get("tool_calls", []), "finish_reason": "stop"}
+
+    return fake_round
+
+
+async def _fake_execute(name: str, args: dict[str, Any], ctx: Any) -> dict[str, Any]:
+    return {"ok": True, "result": {"rows": [], "count": 0}}
+
+
+async def _run(monkeypatch: pytest.MonkeyPatch, tool_calls: list[dict[str, Any]]) -> list[list[dict[str, Any]]]:
+    captured: list[list[dict[str, Any]]] = []
+    script = [{"tool_calls": tool_calls}, {"text_pieces": ["好的"]}]
+    monkeypatch.setattr(chat_service, "ai_configured", lambda: True)
+    monkeypatch.setattr(chat_service, "is_codex_cli_provider", lambda provider=None: False)
+    monkeypatch.setattr(chat_service, "stream_openai_round", _script_round(script, captured))
+    monkeypatch.setattr(assistant_tools, "execute_assistant_tool", _fake_execute)
+
+    lines = [line async for line in chat_service.chat_stream(
+        history=[{"role": "user", "content": "看看贵州茅台"}],
+    )]
+    events = [json.loads(line) for line in lines]
+    assert [e["type"] for e in events if e["type"] == "error"] == []
+    assert len(captured) == 2
+    return captured
+
+
+async def test_missing_tool_call_id_backfill_matches_assistant_message(monkeypatch: pytest.MonkeyPatch) -> None:
+    captured = await _run(monkeypatch, [
+        {"id": "", "name": "get_stock_quote", "arguments": '{"symbols": ["600519.SH"]}'},
+    ])
+
+    second_round = captured[1]
+    assistant_msg, tool_msg = second_round[-2], second_round[-1]
+    call_id = assistant_msg["tool_calls"][0]["id"]
+    assert call_id
+    assert tool_msg["role"] == "tool"
+    assert tool_msg["tool_call_id"] == call_id
+
+
+async def test_parallel_calls_without_ids_get_distinct_matching_ids(monkeypatch: pytest.MonkeyPatch) -> None:
+    captured = await _run(monkeypatch, [
+        {"id": "", "name": "get_stock_quote", "arguments": '{"symbols": ["600519.SH"]}'},
+        {"id": "", "name": "get_stock_daily", "arguments": '{"symbol": "600519.SH"}'},
+    ])
+
+    second_round = captured[1]
+    assistant_msg = second_round[-3]
+    tool_msgs = second_round[-2:]
+    call_ids = [call["id"] for call in assistant_msg["tool_calls"]]
+    assert all(call_ids)
+    assert len(set(call_ids)) == 2
+    assert [m["tool_call_id"] for m in tool_msgs] == call_ids
+
+
+async def test_provider_supplied_tool_call_id_is_kept(monkeypatch: pytest.MonkeyPatch) -> None:
+    captured = await _run(monkeypatch, [
+        {"id": "call_abc", "name": "get_stock_quote", "arguments": '{"symbols": ["600519.SH"]}'},
+    ])
+
+    second_round = captured[1]
+    assert second_round[-2]["tool_calls"][0]["id"] == "call_abc"
+    assert second_round[-1]["tool_call_id"] == "call_abc"