WEBSERVICE Service Now Guide - Everthing you need to know

1xx: Informational
2xx: Success
3xx: Redirection
4xx: Client Error
5xx: Server Error <img src="https://developer.servicenow.com/app_store_learnv2_rest_orlando_inbound_images_inbound_response200.png" alt="The response codes indicate the success or failure of the transaction.">

Request

ServiceNow APIs return standard HTTP status codes. Generally speaking:

Status Code	Message	Details
200	Sucess	Success with responde body
201	Created	Success with responde body
202	Accepted	The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually be acted upon, as it might be disallowed when processing actually takes place.

204	Success	Success with NO responde body
400	Bad Request	The request URI does not match the APIs in the system, or the operation failed for unknown resons. Invalid headers can also cause this error
401	Unauthorized	The user is not authorized to use the API.
403	Forbidden	The request operation is not permitted for the user. This error can also be caused by, ACL failures, or business rule or data policy constraints
404	Not found	The requested resource was not found. This can be caused by an ACL constraint or if the resource does not exist.
405	Method not allowed	The HTTP action is not allowed for the requested REST API, or it is not supported by any API.
406	Not acceptable	The endpoint does not support the response format specified in the request Accept header.
415	Unsupported media type	The endpoint does not support the format of the request body.