Laravel API change unauthenticated message

When making API calls to Laravel when a user who is not authenticated makes a call a 401 status code is returned and the following response:

{"message":"Unauthenticated."}

Which I find a little strange it's an error so message should say error in my opinion.

This can easily be changed by adding a customer unauthenticated method to app/Exceptions/Handler.php:

protected function unauthenticated($request, AuthenticationException $exception) 
{
    if ($request->expectsJson()) {
        return response()->json(['error' => 'Unauthenticated.'], 401);
    }

    return redirect()->guest('login');
}

Now the response will say error instead of message.