What is simple protocol?

Simple protocol is simple:

1. Never intentionally throw exceptions.
2. Return a valid JSON object like this for a success:

{
  success: true,
  payload: {
    // the result of the operation, i.e. an http response body
  }
}

3. Return a valid JSON object like this for an error:

{
  success: false,
  error: {
    // error details or object
  }
}

That's it! Both success and error cases are handled the same way and can follow the same code path.