This is why we developed the Postman Collection format. It's very simple, and expressive. More importantly, it's a way to impose _less_ constraints on the API Designer, while also being richly documented.

Here's an example of a very simple collection: https://github.com/postmanlabs/postman-collection-transforme...

But, you can also go and have something like https://github.com/postmanlabs/postman-collection-transforme..., which is very well documented. The generated documentation for this is available too: https://docs.postman-echo.com

Disclaimer: I work at Postman.