How to properly combine REST API and JSON-RPC 2.0 in one API?

Question

API

Good time, in the course of developing a REST API for web applications, the idea arose of using JSON-RPC 2.0 to perform all operations that are not related to direct CRUD interaction with resources.
For example, using JSON-RPC, one could implement the following requests:

• User authentication followed by return of access_token
  
• Sending a letter on post
  
• Interaction with third party services
  

While for CRUD interaction with resources, regular REST would be used.
Has anyone encountered such a perversion? If so, what pitfalls can arise from the point of view of developing client applications?

Answer 1

Faced, even once did. Only for such hands it is necessary to tear off because it is not REST. Any RPC was originally intended for asynchronous operations when REST is a synchronous protocol