OpenAI videos never fetches input URLs or invents download size caps. Drop MAX_VIDEO_MEDIA_* and the fetch-and-inline path. Keep MAX_IMAGE_URL_DOWNLOAD_SIZE_MB for chat image handling. Validate Omni reference URLs, then send them as form fields the way OpenAI videos sends input_reference as a file
Route hosted_vllm video generation through /v1/videos as multipart form data so Omni extra fields such as width and extra_params reach the server instead of a JSON body Omni rejects