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Co-authored-by: greptile-apps[bot] <165735046+greptile-apps[bot]@users.noreply.github.com>

Author: andrewm4894

posthog/ai/openai/openai_async.py

@@ -449,7 +449,7 @@ async def _capture_streaming_event(
             posthog_trace_id = str(uuid.uuid4())
 
         # Use model from kwargs, fallback to model from response
-        model = kwargs.get("model") or model_from_response
+        model = kwargs.get("model") or model_from_response or "unknown"
 
         event_properties = {
             "$ai_provider": "openai",