Comment by blomqma

Yes, having a decorator-free approach was one of the main reasons why I started working on this - I've currently implemented the OpenAPI instrumentation in a way that all of your endpoints are called with specific headers that make those endpoints return their own API spec, generated from the parameters that they are defined with. While this might sound a bit IO-heavy with a potentially high amount of network requests, it is done only when calling the Swagger UI endpoint and it can be improved with some caching, I think.