HTTP response codes

Overview of the User.com API


HTTP response status codes indicate whether a specific HTTP request has been successfully completed. Responses are grouped in five classes: informational responses, successful responses, redirects, client errors, and servers errors.

All error responses are in the following format, delivered with the corresponding status code:

Error ResponseDescription
400
Bad Request
The request was incorrect, please make sure that passed arguments are matching format in method's documentation.
401
Unauthorized
Unauthorized. You attempt to authenticate with an invalid username or API key.
403
Forbidden
Forbidden. Your request is not allowed.
404
Not Found
Not Found. You attempt to request a resource which doesn't exist.
429
Too Many Requests
Too many requests. You have reached a rate limit.
500
Internal Server Error
Internal Server Error. Something unexpected happened on our end. Please try again or contact support.
502
Bad Gateway
The server, while acting as a gateway or proxy, received an invalid response from an inbound server it accessed while attempting to fulfill the request.
504
Gateway Timeout
The server, while acting as a gateway or proxy, did not receive a timely response from an upstream server it needed to access in order to complete the request.

More on that to be explained here