Add the ability caption the image in the query through some syntax.

I think giphy follows something like /command [query] [#caption], where the optional # is essentially where you'd "split" the query and everything after would be caption.

This will require either Openverse exposing the watermarking API with customizable text or using some image processing library to do it directly in the bot somehow (but this would require hosting the image somewhere so I'd prefer if it was just part of the Openverse thumbnail API or something).