Level 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 charge failed, etc.). Codes in the 5xx range indicate an error with Level's servers (these are rare).

Status Code
200OKThe request was successful.
400Bad RequestThe request failed, often due to a missing parameter.
401UnauthorizedA valid API key was not provided.
404Not FoundThe requested resource does not exist.
500Server ErrorSomething went wrong on Level's end.

The error body will contain a detailed error message about what went wrong:

{
  error: "Error message"
}