Nah, this guy is wrong. The reason that he's wrong is that URLs represent resources, such as, in his example API, employee data. If you submit a request for a resource that doesn't exist, then 404 is the correct response. His problem is in thinking that HTTP is just a transport layer for arbitrary applications to use for whatever they want. It's not; it's a framework for particular types of applications, using REST and HATEOAS. He's trying to write some kind of RPC application using REST syntax, but ignoring REST semantics.