fix: continue after output-length truncation

tests/test_run_agent.py

@@ -829,6 +829,36 @@ class TestRunConversation:
         assert result["final_response"] == "All done"
         assert result["completed"] is True
 
+    @pytest.mark.parametrize(
+        ("first_content", "second_content", "expected_final"),
+        [
+            ("Part 1 ", "Part 2", "Part 1 Part 2"),
+            ("<think>internal reasoning</think>", "Recovered final answer", "Recovered final answer"),
+        ],
+    )
+    def test_length_finish_reason_requests_continuation(
+        self, agent, first_content, second_content, expected_final
+    ):
+        self._setup_agent(agent)
+        first = _mock_response(content=first_content, finish_reason="length")
+        second = _mock_response(content=second_content, finish_reason="stop")
+        agent.client.chat.completions.create.side_effect = [first, second]
+
+        with (
+            patch.object(agent, "_persist_session"),
+            patch.object(agent, "_save_trajectory"),
+            patch.object(agent, "_cleanup_task_resources"),
+        ):
+            result = agent.run_conversation("hello")
+
+        assert result["completed"] is True
+        assert result["api_calls"] == 2
+        assert result["final_response"] == expected_final
+
+        second_call_messages = agent.client.chat.completions.create.call_args_list[1].kwargs["messages"]
+        assert second_call_messages[-1]["role"] == "user"
+        assert "truncated by the output length limit" in second_call_messages[-1]["content"]
+
 
 class TestRetryExhaustion:
     """Regression: retry_count > max_retries was dead code (off-by-one).