Better way to catch authentication errors?

Is there a better way to catch authentication errors? At the moment if I run nexmo.initialize(...) with incorrect credentials the callback for a method does NOT return an error object. Instead the response object looks as follows:

{ 'error-code': '401',
  'error-code-label': 'authentication failed' }

There’s a few things that would be useful here.

1. Catch authentication errors and actually return an error object instead of a response in an API call.
2. Provide a way to validate nexmo.initialize(...) without making an API call

[leggetter]

I meant check that the credentials have been supplied - not that they existing within the Nexmo platform e.g. check for empty strings, null/undefined values and so on.

[cbetta]

Irrelevant due to many changes since this was opened.