fix: address review comments for OpenAI Responses API model

- Add OpenAIResponsesModel to lazy loading in strands.models.__init__.py
- Remove 'Step X:' prefixes from logging to match project conventions
- Fix unused variable in test fixture by removing model_name from params

Author: strands-agent

src/strands/models/__init__.py

@@ -55,6 +55,10 @@ def __getattr__(name: str) -> Any:
         from .openai import OpenAIModel
 
         return OpenAIModel
+    if name == "OpenAIResponsesModel":
+        from .openai_responses import OpenAIResponsesModel
+
+        return OpenAIResponsesModel
     if name == "SageMakerAIModel":
         from .sagemaker import SageMakerAIModel
 

src/strands/models/openai_responses.py

@@ -198,17 +198,17 @@ async def stream(
             ContextWindowOverflowException: If the input exceeds the model's context window.
             ModelThrottledException: If the request is throttled by OpenAI (rate limits).
         """
-        logger.debug("Step 1: formatting request for OpenAI Responses API")
+        logger.debug("formatting request for OpenAI Responses API")
         request = self._format_request(messages, tool_specs, system_prompt, tool_choice)
-        logger.debug("Step 1: formatted request=<%s>", request)
+        logger.debug("formatted request=<%s>", request)
 
-        logger.debug("Step 2: invoking OpenAI Responses API model")
+        logger.debug("invoking OpenAI Responses API model")
 
         async with openai.AsyncOpenAI(**self.client_args) as client:
             try:
                 response = await client.responses.create(**request)
 
-                logger.debug("Step 3: streaming response from OpenAI Responses API model")
+                logger.debug("streaming response from OpenAI Responses API model")
 
                 yield self._format_chunk({"chunk_type": "message_start"})
 
@@ -335,7 +335,7 @@ async def stream(
             if final_usage:
                 yield self._format_chunk({"chunk_type": "metadata", "data": final_usage})
 
-        logger.debug("Step 4: finished streaming response from OpenAI Responses API model")
+        logger.debug("finished streaming response from OpenAI Responses API model")
 
     @override
     async def structured_output(

tests_integ/models/test_model_openai.py

@@ -17,12 +17,12 @@
 
 @pytest.fixture(
     params=[
-        ("openai", OpenAIModel, "gpt-4o"),
-        ("openai_responses", OpenAIResponsesModel, "gpt-4o"),
+        (OpenAIModel, "gpt-4o"),
+        (OpenAIResponsesModel, "gpt-4o"),
     ]
 )
 def model(request):
-    model_name, model_class, model_id = request.param
+    model_class, model_id = request.param
     return model_class(
         model_id=model_id,
         client_args={