Technically, there are REST/JSON equivalents, but I don't see them actually used much in the wild - so much of the time with REST APIs you are stuck with whatever half-baked, out-of-date documentation that somebody may or may not have written, or just randomly poking at it through trial and error to discover how it works.
Agreed WSDLs are the only thing I love about SOAP and they are missing from REST. Most tools can import a WSDL and generate the code and structure for you.
Sometimes even getting a sample of the expected JSON format can be hard. If you’re not versioning you’re APIs you can break everything if the schema changes.
I used to debate this with the SOA manager. Swagger looks ok but never dealt with it in production or saw it in the wild with our customers.
Technically, there are REST/JSON equivalents, but I don't see them actually used much in the wild - so much of the time with REST APIs you are stuck with whatever half-baked, out-of-date documentation that somebody may or may not have written, or just randomly poking at it through trial and error to discover how it works.