diff --git a/litellm/llms/openai/responses/transformation.py b/litellm/llms/openai/responses/transformation.py
index 047572657c..bff03c64f5 100644
--- a/litellm/llms/openai/responses/transformation.py
+++ b/litellm/llms/openai/responses/transformation.py
@@ -56,7 +56,9 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig):
         drop_params: bool,
     ) -> Dict:
         """No mapping applied since inputs are in OpenAI spec already"""
-        return dict(response_api_optional_params)
+        temp = dict(response_api_optional_params)
+        temp.pop("reasoning")
+        return temp
 
     def transform_responses_api_request(
         self,
diff --git a/litellm/proxy/proxy_config.yaml b/litellm/proxy/proxy_config.yaml
index 17658df903..158642ab72 100644
--- a/litellm/proxy/proxy_config.yaml
+++ b/litellm/proxy/proxy_config.yaml
@@ -1,6 +1,8 @@
 model_list:
-  - model_name: fake-openai-endpoint
+  - model_name: o4-mini
     litellm_params:
-      model: openai/fake
-      api_key: fake-key
-      api_base: https://exampleopenaiendpoint-production.up.railway.app/
+      model: azure/computer-use-preview
+      truncation: auto
+      api_base: os.environ/AZURE_RESPONSES_OPENAI_ENDPOINT
+      api_key: os.environ/AZURE_RESPONSES_OPENAI_API_KEY
+      api_version: os.environ/AZURE_RESPONSES_OPENAI_API_VERSION