Stop repeated duplicate skill loops

tests/test_agent_runtime.py

@@ -1386,6 +1386,84 @@ class AgentRuntimeTests(unittest.TestCase):
         duplicate_payload = json.loads(str(tool_messages[1].get('content', '{}')))
         self.assertIn('已在本轮激活', duplicate_payload.get('content', ''))
 
+    def test_agent_stops_repeated_duplicate_skill_loop(self) -> None:
+        skill_call = {
+            'type': 'function',
+            'function': {
+                'name': 'Skill',
+                'arguments': '{"skill": "verify"}',
+            },
+        }
+        responses = [
+            {
+                'choices': [
+                    {
+                        'message': {
+                            'role': 'assistant',
+                            'content': 'I will load the verification skill.',
+                            'tool_calls': [{**skill_call, 'id': 'call_1'}],
+                        },
+                        'finish_reason': 'tool_calls',
+                    }
+                ],
+                'usage': {'prompt_tokens': 8, 'completion_tokens': 3},
+            },
+            {
+                'choices': [
+                    {
+                        'message': {
+                            'role': 'assistant',
+                            'content': 'I accidentally load it again.',
+                            'tool_calls': [{**skill_call, 'id': 'call_2'}],
+                        },
+                        'finish_reason': 'tool_calls',
+                    }
+                ],
+                'usage': {'prompt_tokens': 8, 'completion_tokens': 3},
+            },
+            {
+                'choices': [
+                    {
+                        'message': {
+                            'role': 'assistant',
+                            'content': 'I am still stuck loading it again.',
+                            'tool_calls': [{**skill_call, 'id': 'call_3'}],
+                        },
+                        'finish_reason': 'tool_calls',
+                    }
+                ],
+                'usage': {'prompt_tokens': 8, 'completion_tokens': 3},
+            },
+        ]
+        recorded_payloads: list[dict[str, object]] = []
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            workspace = Path(tmp_dir)
+            with patch(
+                'src.openai_compat.request.urlopen',
+                side_effect=make_recording_urlopen_side_effect(responses, recorded_payloads),
+            ):
+                agent = LocalCodingAgent(
+                    model_config=ModelConfig(
+                        model='Qwen/Qwen3-Coder-30B-A3B-Instruct',
+                        base_url='http://127.0.0.1:8000/v1',
+                    ),
+                    runtime_config=AgentRuntimeConfig(cwd=workspace, max_turns=50),
+                )
+                result = agent.run('Use verify skill')
+
+        self.assertEqual(len(recorded_payloads), 3)
+        self.assertEqual(result.stop_reason, 'duplicate_skill_loop')
+        self.assertIn('连续重复调用 Skill', result.final_output)
+        self.assertEqual(result.tool_calls, 3)
+        tool_messages = [
+            message for message in result.transcript if message.get('role') == 'tool'
+        ]
+        self.assertEqual(tool_messages[-1].get('metadata', {}).get('stop_agent'), True)
+        self.assertEqual(tool_messages[-1].get('metadata', {}).get('duplicate_count'), 2)
+        self.assertTrue(
+            any(event.get('type') == 'tool_requested_stop' for event in result.events)
+        )
+
     def test_agent_records_file_history_for_write_tool(self) -> None:
         responses = [
             {