GitBook uses conventional HTTP response codes to indicate the success or failure of an API request.
As a general rule:
  • Codes in the 2xx range indicate success.
  • Codes in the 4xx range indicate incorrect or incomplete parameters (e.g. a required parameter was omitted, or an operation failed with a 3rd party, etc.).
  • Codes in the 5xx range indicate an error with GitBook's servers.
GitBook also outputs an error message and an error code formatted in JSON:
"error": {
"code": 404,
"message": "Page not found in this space"