UltraCart uses conventional HTTP response codes to indicate the success or failure of an API request. In general, codes in the 2xx range indicate success, codes in the 4xx range indicate an error that failed given the information provided (e.g., a required parameter was omitted, a value is inappropriate, your requests are happening at too fast a rate, etc.), and codes in the 5xx range indicate an error with UltraCart's servers (these are rare). Most API responses will contain the following attributes:
In addition to returning a non-2xx HTTP response code, the response body will be a JSON object with these particular fields populated. This allows you a more granular understanding of the error that is returned.