The difference is that a real HATEOAS API provides clients with context through the payload for all service interactions. HTTP becomes just the transport layer.

The difference is that a real HATEOAS API provides clients with context through the payload for all service interactions. HTTP becomes just the transport layer. Roy Fielding never wanted to point to anything else. He was inspired by how HTML enabled human-to-service interaction through a Browser (the client) and formulated an architectural style for human/machine-to-service interaction. The emphasis must be on how we design formats. Communicating the state is just freestyle, HTTP being the prominent one.