Conventional HTTP response codes are used to indicate success or failure of a request.

Response CodeDescription
200 OKEverything worked as expected.
201 CreatedOrder object successfully created.
400 Bad RequestGeneral client error, usually because of missing or malformed data.
401 UnauthorizedThe API Key was not authorized.
404 Not FoundThe requested resource was not found.
409 ConflictThe request could not be completed due to a conflict with the current state of the resource.
500, 502, 503, 504Server errors.