Errors

When a call fails, res is "error", and the response includes a numeric code and a human-readable message:

{
  "res": "error",
  "code": "102",
  "message": "Field(s) is (are) required but not found."
}

Error codes are unique per method. The leading digits identify the method:

Codes	Method
1xx	Add order
2xx	Reorder
3xx	Hold order
4xx	Unhold order
5xx	Cancel order
6xx	Change shipping address
7xx	Change shipping method
8xx	Change shipping deadline
9xx	Get status
10xx	Shipping rate
11xx	Package information
12xx	Enable rush processing

Each method's page lists its full set of error codes.

Common errors

Error	What to do
Authentication failed (x01)	Check your username, password and secretkey, and that you're using the right credentials for the environment.
Missing field (x02)	Check that you've sent every required field in data.
Invalid arguments (HTTP 400)	The request body isn't valid JSON, or the Content-Type: application/json header is missing.