The API uses HTTP status codes to indicate an error has occurred while processing a request.

400Either a malformed request, or a missing or invalid parameter was passed. Often with 400 errors related to parameters, we'll return a broad description of the issue.
401The request could not be authenticated
403The user is not authorized to access the requested resource
404Either the request was made to an incorrect endpoint, or the requested resource doesn't exist
429We've received too many API requests from this account over the last hour