fix(vertex): mirror vertex_ai_safety_results on assembled streaming responses

The non-streaming transform_response stores safety data under
vertex_ai_safety_results, but the streaming path only wrote
vertex_ai_safety_ratings. Assembled streaming responses therefore never
carried vertex_ai_safety_results, so any consumer reading that field saw
a silent difference between streaming and non-streaming calls.

Set vertex_ai_safety_results alongside vertex_ai_safety_ratings in the
shared stream metadata setter and add it to the assembled metadata field
list so it propagates through stream_chunk_builder.

litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py

@@ -2257,6 +2257,7 @@ class VertexGeminiConfig(VertexAIBaseConfig, BaseConfig):
         "vertex_ai_grounding_metadata",
         "vertex_ai_url_context_metadata",
         "vertex_ai_safety_ratings",
+        "vertex_ai_safety_results",
         "vertex_ai_citation_metadata",
     )
 
@@ -2296,8 +2297,10 @@ class VertexGeminiConfig(VertexAIBaseConfig, BaseConfig):
                 url_context_metadata
             )
         setattr(model_response, "vertex_ai_safety_ratings", safety_ratings)  # type: ignore
+        setattr(model_response, "vertex_ai_safety_results", safety_ratings)  # type: ignore
         if safety_ratings:
             model_response._hidden_params["vertex_ai_safety_ratings"] = safety_ratings
+            model_response._hidden_params["vertex_ai_safety_results"] = safety_ratings
         setattr(model_response, "vertex_ai_citation_metadata", citation_metadata)  # type: ignore
         if citation_metadata:
             model_response._hidden_params["vertex_ai_citation_metadata"] = (

tests/test_litellm/litellm_core_utils/test_streaming_chunk_builder_utils.py

@@ -705,6 +705,37 @@ def test_stream_chunk_builder_uses_assembled_model_for_provider_metadata():
     assert getattr(response, "vertex_ai_grounding_metadata") == grounding_metadata
 
 
+def test_stream_chunk_builder_propagates_vertex_ai_safety_results():
+    """Assembled response must expose safety data under the non-streaming field name."""
+    safety_ratings = [
+        [{"category": "HARM_CATEGORY_HATE_SPEECH", "probability": "NEGLIGIBLE"}]
+    ]
+
+    chunk = ModelResponseStream(
+        id="chatcmpl-vertex-safety",
+        created=1,
+        model="gemini-2.5-flash",
+        object="chat.completion.chunk",
+        choices=[
+            StreamingChoices(
+                finish_reason="stop",
+                index=0,
+                delta=Delta(content="hello", role="assistant"),
+            )
+        ],
+    )
+    setattr(chunk, "vertex_ai_safety_ratings", safety_ratings)
+    setattr(chunk, "vertex_ai_safety_results", safety_ratings)
+    chunk._hidden_params["vertex_ai_safety_ratings"] = safety_ratings
+    chunk._hidden_params["vertex_ai_safety_results"] = safety_ratings
+
+    response = stream_chunk_builder(chunks=[chunk])
+    assert response is not None
+    assert getattr(response, "vertex_ai_safety_results") == safety_ratings
+    assert response._hidden_params["vertex_ai_safety_results"] == safety_ratings
+    assert response.model_dump()["vertex_ai_safety_results"] == safety_ratings
+
+
 def test_stream_chunk_builder_propagates_vertex_ai_metadata_from_dict_chunks():
     """Dict snapshot chunks (model_dump) should also propagate Vertex AI metadata."""
     chunk_dict = ModelResponseStream(

tests/test_litellm/llms/vertex_ai/gemini/test_vertex_and_google_ai_studio_gemini.py

@@ -1459,6 +1459,26 @@ def test_vertex_ai_process_candidates_with_grounding_metadata():
     assert len(result[0]) == 1
 
 
+def test_set_stream_metadata_mirrors_non_streaming_safety_field_names():
+    safety_ratings = [
+        [{"category": "HARM_CATEGORY_HATE_SPEECH", "probability": "NEGLIGIBLE"}]
+    ]
+
+    model_response = ModelResponse()
+    VertexGeminiConfig._set_stream_metadata_on_response(
+        model_response=model_response,
+        grounding_metadata=[],
+        url_context_metadata=[],
+        safety_ratings=safety_ratings,
+        citation_metadata=[],
+    )
+
+    assert getattr(model_response, "vertex_ai_safety_ratings") == safety_ratings
+    assert getattr(model_response, "vertex_ai_safety_results") == safety_ratings
+    assert model_response._hidden_params["vertex_ai_safety_ratings"] == safety_ratings
+    assert model_response._hidden_params["vertex_ai_safety_results"] == safety_ratings
+
+
 def test_vertex_ai_tool_call_id_format():
     """
     Test that tool call IDs have the correct format and length.