> What REST has given us is an industry-wide lingua franca. At the basic level, it's a basic understanding of how to map nouns/verbs to HTTP verbs and URLs. Users get to use the basic HTTP response codes. There's still a ton of design and subtlety to all this. Do you really get to do things that are technically allowed, but might break at a typical load balancer (returning bodies with certain error codes)? Is your returning 500 retriable in all cases, with what preferred backoff behavior?

What was wrong with all nouns and verbs map to POST (maybe sometimes GET), and HTTP response codes other than 200 mean your request failed somewhere between the client code and the application server code. HTTP 200 means the application server processed the request and you can check the payload for an application indicator of success, failure, and/or partial success. If you work with enough systems, you end up going back to this, because least common denominator works everywhere.

Either way, anything that isn't ***** SOAP is a good start.