I’m invested in it. I’m using it to provide implementation-specific validation of requests to/from a third party API.
I wish there was a good macOS editor or IDEA plugin for it with autocomplete etc. The static generators from examples are obscure, ugly, minimal, and can’t account for variations. It isn’t pleasant to write, it’s tedious and slow.
Nevertheless I’d rather write API validation this way, in a document, than in code.