Выдержка из API pushbullet:

Errors

Error responses (any non-200 error code) contain information on the kind of error that happened. The response JSON will have an error property with the following fields:

    type - A machine-readable code to refer to this type of error. Either invalid_request for client side errors or server for server side errors.
    message - A (mostly) human-readable error message.
    param - (OPTIONAL) Appears sometimes during an invalid_request error to say which parameter in the request caused the error.
    cat - Some sort of ASCII cat to offset the pain of receiving an error message.

поле cat просто превосходно.

EXAMPLE ERROR

{
  "error": {
      "message": "The resource could not be found.",
      "type": "invalid_request",
      "cat": "~(=^‥^)"
  }

}