add a test

Author: xzrderek

tests/test_litellm_policy_provider_fields.py

@@ -0,0 +1,95 @@
+import types
+
+import pytest
+
+import eval_protocol.mcp.execution.policy as policy_mod
+from eval_protocol.mcp.execution.policy import LiteLLMPolicy
+
+
+@pytest.mark.asyncio
+async def test_litellm_policy_surfaces_provider_specific_reasoning_details(monkeypatch):
+    """
+    Ensure that provider_specific_fields from the LiteLLM message object are
+    preserved on the returned message dict from LiteLLMPolicy._make_llm_call.
+    """
+
+    # Define a fake ModelResponse base class and patch the module's ModelResponse
+    class FakeModelResponseBase: ...
+
+    policy_mod.ModelResponse = FakeModelResponseBase
+
+    async def fake_acompletion(*args, **kwargs):
+        # This mimics the LiteLLM Message object shape we rely on in policy._make_llm_call
+        message_obj = types.SimpleNamespace(
+            role="assistant",
+            content="",
+            tool_calls=[
+                types.SimpleNamespace(
+                    id="tool_get_reservation_details_123",
+                    type="function",
+                    function=types.SimpleNamespace(
+                        name="get_reservation_details",
+                        arguments='{"reservation_id":"EHGLP3"}',
+                    ),
+                )
+            ],
+            provider_specific_fields={
+                "reasoning_details": [{"id": "tool_get_reservation_details_123", "type": "reasoning.encrypted"}],
+                "custom_field": "keep_me",
+            },
+        )
+
+        class FakeModelResponse(FakeModelResponseBase):
+            def __init__(self) -> None:
+                self.choices = [
+                    types.SimpleNamespace(
+                        finish_reason="tool_calls",
+                        index=0,
+                        message=message_obj,
+                    )
+                ]
+                self.usage = types.SimpleNamespace(
+                    prompt_tokens=10,
+                    completion_tokens=5,
+                    total_tokens=15,
+                )
+
+        return FakeModelResponse()
+
+    # Patch acompletion so we don't hit the network
+    monkeypatch.setattr(policy_mod, "acompletion", fake_acompletion)
+
+    # Use a concrete policy instance; base_url/model_id values don't matter for this unit test
+    policy = LiteLLMPolicy(model_id="openrouter/google/gemini-3-pro-preview", use_caching=False)
+
+    messages = [
+        {
+            "role": "assistant",
+            "content": "",
+            "tool_calls": [
+                {
+                    "id": "tool_get_reservation_details_123",
+                    "type": "function",
+                    "function": {"name": "get_reservation_details", "arguments": '{"reservation_id":"EHGLP3"}'},
+                }
+            ],
+        }
+    ]
+
+    # No tools are needed for this test – we only care about the returned message shape
+    result = await policy._make_llm_call(messages, tools=[])
+
+    assert "choices" in result
+    assert len(result["choices"]) == 1
+    msg = result["choices"][0]["message"]
+
+    # Core fields should be present
+    assert msg["role"] == "assistant"
+    assert isinstance(msg.get("tool_calls"), list)
+
+    # provider_specific_fields should be preserved on the message
+    ps = msg.get("provider_specific_fields")
+    assert isinstance(ps, dict)
+    assert ps["reasoning_details"] == [{"id": "tool_get_reservation_details_123", "type": "reasoning.encrypted"}]
+    # Non-core provider_specific_fields should also be preserved
+    assert ps.get("custom_field") == "keep_me"