Location of an image referenced by an ImageUrlPart.
How much of the image's resolution reaches the model; defaults to the API's own choice when left unset.
Either an http(s) link the API fetches, or a base64 data URL that inlines the image (data:image/jpeg;base64,...). JPEG, PNG, GIF and WebP are supported.
http(s)
data:image/jpeg;base64,...