I've been thinking about using an OpenAPI schema to describe cli tools. It would probably need extensions to describe stdin/stout and other things that don't happen in REST.
Have you seen Stainless's CLI generator?
https://www.stainless.com/blog/stainless-cli-generator-your-...
Have you seen Stainless's CLI generator?
https://www.stainless.com/blog/stainless-cli-generator-your-...