diff --git a/litellm/types/llms/openai.py b/litellm/types/llms/openai.py
index 0369ed1e204..980bdd6fde4 100644
--- a/litellm/types/llms/openai.py
+++ b/litellm/types/llms/openai.py
@@ -44,7 +44,7 @@ from openai.types.responses.response import (
 # Handle OpenAI SDK version compatibility for Text type
 try:
     # fmt: off
-    from openai.types.responses.response_create_params import ( # type: ignore[attr-defined]
+    from openai.types.responses.response_create_params import (
         Text as ResponseText,  # type: ignore[attr-defined]
     )
 
@@ -1053,11 +1053,11 @@ class ResponsesAPIResponse(BaseLiteLLMOpenAIResponseObject):
         List[Union[ResponseOutputItem, Dict]],
         List[Union[GenericResponseOutputItem, OutputFunctionToolCall]],
     ]
-    parallel_tool_calls: bool
+    parallel_tool_calls: Optional[bool] = None
     temperature: Optional[float] = None
-    tool_choice: ToolChoice
-    tools: Union[List[Tool], List[ResponseFunctionToolCall], List[Dict[str, Any]]]
-    top_p: Optional[float]
+    tool_choice: Optional[ToolChoice] = None
+    tools: Optional[Union[List[Tool], List[ResponseFunctionToolCall], List[Dict[str, Any]]]] = None
+    top_p: Optional[float] = None
     max_output_tokens: Optional[int] = None
     previous_response_id: Optional[str] = None
     reasoning: Optional[Reasoning] = None
diff --git a/tests/llm_responses_api_testing/base_responses_api.py b/tests/llm_responses_api_testing/base_responses_api.py
index afb30f15f08..9a77ca6b683 100644
--- a/tests/llm_responses_api_testing/base_responses_api.py
+++ b/tests/llm_responses_api_testing/base_responses_api.py
@@ -57,9 +57,6 @@ def validate_responses_api_response(response, final_chunk: bool = False):
     assert "output" in response and isinstance(
         response["output"], list
     ), "Response should have a list 'output' field"
-    assert "parallel_tool_calls" in response and isinstance(
-        response["parallel_tool_calls"], bool
-    ), "Response should have a boolean 'parallel_tool_calls' field"
 
     # Optional fields with their expected types
     optional_fields = {
@@ -69,9 +66,10 @@ def validate_responses_api_response(response, final_chunk: bool = False):
         "metadata": dict,
         "model": str,
         "object": str,
+        "parallel_tool_calls": (bool, type(None)),
         "temperature": (int, float, type(None)),
-        "tool_choice": (dict, str),
-        "tools": list,
+        "tool_choice": (dict, str, type(None)),
+        "tools": (list, type(None)),
         "top_p": (int, float, type(None)),
         "max_output_tokens": (int, type(None)),
         "previous_response_id": (str, type(None)),