On an HTTP module, if you turn on the "Evaluate all states as errors (except for 2xx and 3xx)" option and the request returns an error code, there is no way to process the body of that response. Some services add extra context about the error in the body of a 4XX-5XX code.
This will allow you to do multiple things, such as:
  1. Set proper routing based on the message.
  2. Save a record of the specifics of the error.
  3. Handle error responses in a more efficient and quick way.
Thanks!