can you explain that example more clearly?

if you wanted to "include images or something of that sort" you would add an "images" key or a "something of that sort" key

in your particular example, body can clearly take image links image data as string and the parser can deal with it.

in my projects we typically would have a nosql database which out the box allows it to be indifferent about objects in a collection/table that include or exclude certain keys