Failure
If an un-recoverable failure occurs during the authentication process the server will send a response with the type property value fail and generally some kind of error object that in some way explains what went wrong. The only reasonable thing for the UI to do in this situation is to display the error message and allow the user to start over.
HTTP/1.1 200 OK
Content-Type: application/json
{
"type": "fail",
"id": "931c4a40-2dc9-11e6-937b-005056c00008",
"error": {
"type": "simple",
"message": "Unable to complete the authentication process. Please try again later"
}
}