How to change the default error output in restify

Is there any way that I can change the default error output? Say I'm going to change the rest error output:

{
    "code": "InvalidArgumentError",
    "message": "blah blah..."
}

to:

{
    "code": 10001,
    "message": "blah blah",
    "extraMsg": "blah blah"
}

Here are some of my ideas:

• Listen to the error events.
  It seems like not all the RestError have emitted extra events (like NotFound, MethodNotAllowed, VersionNotAllowed... do). So I can't catch all the errors to rewrite them.

• Listen to an event before response data sent.
  I look through the official documents and have found nothing relative.

• Modify the implementation of the RestError class.
  Well it's obviously not a good approach.

Any other ideas?