diff --git a/litellm/types/llms/openai.py b/litellm/types/llms/openai.py
index 3ecf58c0b86..4912f9f1375 100644
--- a/litellm/types/llms/openai.py
+++ b/litellm/types/llms/openai.py
@@ -1814,7 +1814,7 @@ class ContentPartDonePartOutputText(BaseLiteLLMOpenAIResponseObject):
     type: Literal["output_text"]
     text: str
     annotations: list[BaseLiteLLMOpenAIResponseObject]
-    logprobs: list[OpenAIChatCompletionLogprobsContent] | None
+    logprobs: list[OpenAIChatCompletionLogprobsContent] | None = None
 
 
 class ContentPartDonePartRefusal(BaseLiteLLMOpenAIResponseObject):
diff --git a/tests/unit/llms/openai/responses/test_openai_responses_http.py b/tests/unit/llms/openai/responses/test_openai_responses_http.py
index 97067881faf..73a45eacf3a 100644
--- a/tests/unit/llms/openai/responses/test_openai_responses_http.py
+++ b/tests/unit/llms/openai/responses/test_openai_responses_http.py
@@ -13,6 +13,7 @@ from pydantic import BaseModel, TypeAdapter
 import litellm
 from litellm.integrations.custom_logger import CustomLogger
 from litellm.types.llms.openai import (
+    ContentPartDonePartOutputText,
     IncompleteDetails,
     ResponseAPIUsage,
     ResponseCompletedEvent,
@@ -225,10 +226,12 @@ def _assert_valid_stream(events: tuple[object, ...], item_id: str) -> None:
     }
     assert getattr(events[4], "delta", None) == _OUTPUT_TEXT
     assert getattr(events[5], "text", None) == _OUTPUT_TEXT
+    assert isinstance(getattr(events[6], "part", None), ContentPartDonePartOutputText)
     assert _json_object(getattr(events[6], "part", None)) == {
         "type": "output_text",
         "text": _OUTPUT_TEXT,
         "annotations": [],
+        "logprobs": None,
     }
     assert getattr(getattr(events[7], "item", None), "type", None) == "message"
     assert tuple(item.id for item in completed.response.output) == (item_id,)
diff --git a/tests/unit/types/llms/test_types_llms_openai.py b/tests/unit/types/llms/test_types_llms_openai.py
index e90d48b64af..6d5f8fabaed 100644
--- a/tests/unit/types/llms/test_types_llms_openai.py
+++ b/tests/unit/types/llms/test_types_llms_openai.py
@@ -8,7 +8,10 @@ import json
 
 import litellm
 from litellm.types.llms.openai import (
+    ContentPartDoneEvent,
+    ContentPartDonePartOutputText,
     HttpxBinaryResponseContent,
+    OpenAIChatCompletionLogprobsContent,
     OpenAIModerationResponse,
     OpenAIVideoObject,
     ResponseCompletedEvent,
@@ -76,6 +79,38 @@ def test_output_item_added_event():
     assert event.item is None
 
 
+@pytest.mark.parametrize(
+    ("include_logprobs", "logprobs"),
+    (
+        (False, None),
+        (True, None),
+        (True, []),
+        (True, [{"token": "hello", "logprob": -0.5, "top_logprobs": []}]),
+    ),
+    ids=("missing", "null", "empty", "values"),
+)
+def test_content_part_done_preserves_typed_text_with_optional_logprobs(
+    include_logprobs: bool, logprobs: list[OpenAIChatCompletionLogprobsContent] | None
+) -> None:
+    event: Final = ContentPartDoneEvent.model_validate(
+        {
+            "type": "response.content_part.done",
+            "item_id": "msg_test",
+            "output_index": 0,
+            "content_index": 0,
+            "part": {
+                "type": "output_text",
+                "text": "hello",
+                "annotations": [],
+                **({"logprobs": logprobs} if include_logprobs else {}),
+            },
+        }
+    )
+    assert isinstance(event.part, ContentPartDonePartOutputText)
+    assert event.part.text == "hello"
+    assert event.part.logprobs == logprobs
+
+
 class TestResponsesAPIResponseOutputText:
     """Tests for the output_text property on ResponsesAPIResponse"""