fix(guardrails): stop labelling image-only input as a not_run scoping skip

Images without text were never dispatched to guardrails before this change, so that gap is not a message scoping skip and must not get a not_run entry

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/llms/openai/chat/guardrail_translation/handler.py

@@ -210,7 +210,7 @@ class OpenAIChatCompletionsHandler(BaseTranslation):
                         task_mappings=tool_call_task_mappings,
                     )
 
-        elif not guardrail_to_apply.records_own_guardrail_information:
+        elif not images_to_check and not guardrail_to_apply.records_own_guardrail_information:
             guardrail_to_apply.add_standard_logging_guardrail_information_to_request_data(
                 guardrail_json_response="no scannable content after message scoping",
                 request_data=data,

tests/test_litellm/llms/openai/chat/guardrail_translation/test_openai_guardrail_handler.py

@@ -1942,6 +1942,27 @@ class TestNoScannableContentRecordsNotRun:
         assert guardrail.last_inputs is not None
         assert all(e.get("guardrail_status") != "not_run" for e in self._recorded_entries(data))
 
+    @pytest.mark.asyncio
+    async def test_image_only_content_is_not_reported_as_not_run(self):
+        """Images are only scanned alongside text, so an image-only request is a
+        pre-existing scan gap, not a message-scoping skip, and must not be labelled one"""
+        handler = OpenAIChatCompletionsHandler()
+        guardrail = MockGuardrail(guardrail_name="image-guardrail")
+        guardrail.skip_system_message_in_guardrail = True
+        data = {
+            "messages": [
+                {"role": "system", "content": "SYSTEM-PROMPT"},
+                {
+                    "role": "user",
+                    "content": [{"type": "image_url", "image_url": {"url": "https://example.com/cat.png"}}],
+                },
+            ]
+        }
+
+        await handler.process_input_messages(data=data, guardrail_to_apply=guardrail)
+
+        assert self._recorded_entries(data) == []
+
 
 class TestBuildBlockSseChunks:
     """build_block_sse_chunks turns a streaming ModifyResponseException into 200 SSE chunks"""