fix agent tool call history ordering

2026-09-05 07:27:15 +08:00 · 2026-05-26 16:42:52 +08:00
parent ccbcce0573
commit 31554bdcb5
2 changed files with 148 additions and 29 deletions
@@ -0,0 +1,89 @@
+import asyncio
+import unittest
+
+from langchain_core.messages import AIMessage, HumanMessage, ToolMessage
+
+from app.agent.middleware.patch_tool_calls import PatchToolCallsMiddleware
+
+
+def _build_tool_call(tool_call_id: str = "call_1", name: str = "search") -> dict:
+    """构造测试用工具调用。"""
+    return {
+        "id": tool_call_id,
+        "type": "tool_call",
+        "name": name,
+        "args": {},
+    }
+
+
+class TestPatchToolCallsMiddleware(unittest.TestCase):
+    """测试工具调用历史修复中间件。"""
+
+    def test_adds_missing_tool_messages_immediately_after_ai_message(self):
+        """缺失工具响应时应立即补齐 ToolMessage。"""
+        middleware = PatchToolCallsMiddleware()
+        messages = [
+            HumanMessage(content="查天气"),
+            AIMessage(content="", tool_calls=[_build_tool_call()]),
+            HumanMessage(content="不用查了"),
+        ]
+
+        result = middleware.before_agent({"messages": messages}, runtime=None)
+
+        patched_messages = result["messages"].value
+        self.assertIs(patched_messages[1], messages[1])
+        self.assertIsInstance(patched_messages[2], ToolMessage)
+        self.assertEqual(patched_messages[2].tool_call_id, "call_1")
+        self.assertIs(patched_messages[3], messages[2])
+
+    def test_moves_late_tool_messages_next_to_matching_ai_message(self):
+        """乱序工具响应应移动到对应 assistant 消息之后。"""
+        middleware = PatchToolCallsMiddleware()
+        tool_message = ToolMessage(content="晴天", tool_call_id="call_1")
+        messages = [
+            HumanMessage(content="查天气"),
+            AIMessage(content="", tool_calls=[_build_tool_call()]),
+            HumanMessage(content="再问一句"),
+            tool_message,
+        ]
+
+        result = middleware.before_agent({"messages": messages}, runtime=None)
+
+        patched_messages = result["messages"].value
+        self.assertIs(patched_messages[1], messages[1])
+        self.assertIs(patched_messages[2], tool_message)
+        self.assertIs(patched_messages[3], messages[2])
+        self.assertNotIn(tool_message, patched_messages[4:])
+
+    def test_drops_orphan_tool_messages(self):
+        """孤立工具响应不应继续进入模型请求历史。"""
+        middleware = PatchToolCallsMiddleware()
+        orphan_tool_message = ToolMessage(content="晴天", tool_call_id="call_orphan")
+        messages = [
+            HumanMessage(content="查天气"),
+            orphan_tool_message,
+            HumanMessage(content="继续"),
+        ]
+
+        result = middleware.before_agent({"messages": messages}, runtime=None)
+
+        patched_messages = result["messages"].value
+        self.assertEqual([msg.type for msg in patched_messages], ["human", "human"])
+        self.assertNotIn(orphan_tool_message, patched_messages)
+
+    def test_async_hook_normalizes_messages(self):
+        """异步 Agent 执行入口也应修复工具调用历史。"""
+        middleware = PatchToolCallsMiddleware()
+        messages = [
+            HumanMessage(content="查天气"),
+            AIMessage(content="", tool_calls=[_build_tool_call()]),
+        ]
+
+        result = asyncio.run(middleware.abefore_agent({"messages": messages}, runtime=None))
+
+        patched_messages = result["messages"].value
+        self.assertEqual([msg.type for msg in patched_messages], ["human", "ai", "tool"])
+
+
+if __name__ == "__main__":
+    unittest.main()