fix: avoid dual gemini thinking controls

providers/gemini/request.py

@@ -53,7 +53,6 @@ def build_request_body(request_data: Any, *, thinking_enabled: bool) -> dict:
         extra_body.update(deepcopy(request_extra))
 
     if thinking_enabled:
-        body["reasoning_effort"] = "high"
         _apply_thinking_config(extra_body)
     else:
         body["reasoning_effort"] = "none"

tests/providers/test_gemini.py

@@ -99,7 +99,7 @@ def test_build_request_body_basic(gemini_provider):
 
     assert body["model"] == "gemini-2.5-flash"
     assert body["messages"][0]["role"] == "system"
-    assert body["reasoning_effort"] == "high"
+    assert "reasoning_effort" not in body
     eb = body.get("extra_body")
     assert isinstance(eb, dict)
     literal_extra_body = eb.get("extra_body")
@@ -119,6 +119,7 @@ def test_build_request_body_sdk_wire_json_has_literal_extra_body(gemini_provider
     body = gemini_provider._build_request_body(req)
     wire_json = _simulate_openai_sdk_wire_json(body)
 
+    assert "reasoning_effort" not in wire_json
     assert "google" not in wire_json
     literal_extra_body = wire_json.get("extra_body")
     assert isinstance(literal_extra_body, dict)
@@ -153,6 +154,7 @@ def test_build_request_body_preserves_caller_extra_body(gemini_provider):
 
     body = gemini_provider._build_request_body(req)
 
+    assert "reasoning_effort" not in body
     eb = body.get("extra_body")
     assert isinstance(eb, dict)
     assert eb.get("metadata") == {"user": "u1"}
@@ -177,6 +179,7 @@ def test_build_request_body_merges_caller_nested_google(gemini_provider):
 
     body = gemini_provider._build_request_body(req)
 
+    assert "reasoning_effort" not in body
     eb = body.get("extra_body")
     assert isinstance(eb, dict)
     assert eb.get("metadata") == {"user": "u1"}
@@ -221,6 +224,17 @@ async def test_stream_response_text(gemini_provider):
         assert any(
             '"text_delta"' in event and "Hello back!" in event for event in events
         )
+        kwargs = mock_create.call_args.kwargs
+        assert "reasoning_effort" not in kwargs
+        extra_body = kwargs.get("extra_body")
+        assert isinstance(extra_body, dict)
+        literal_extra_body = extra_body.get("extra_body")
+        assert isinstance(literal_extra_body, dict)
+        google = literal_extra_body.get("google")
+        assert isinstance(google, dict)
+        thinking_config = google.get("thinking_config")
+        assert isinstance(thinking_config, dict)
+        assert thinking_config.get("include_thoughts") is True
 
 
 @pytest.mark.asyncio