site
The site used to generate the meme. This is set by default if template is an object of class meme_template. One of imgflip, memegenerator (the default, only currently supported), memecaptain, or imgur.
type
If site is memegenerator, optionally one of new, popular (the implicit default), trending, or topic to return a different subset of template images. For trending and topic, query should specify an image name or search term, respectively.
query
When site is memegenerator and type is trending or topic, query should specify an image name or search term, respectively.