API endpoints

As stated, a REST api communicates using endpoints, that serve different purposes. All endpoints are named in a logical fashion so they (at least somewhat) let you know what function they are ment for.
For instance: the /key/ endpoint is for dealing with keys, /shipments/ for dealing with shipments, etc.

In each endpoint, there are different methods possible (GET, POST, etc), and some even have extensions to the URL (like adding an ID, or subfunction).
Each method and each (sub)function will be listed at the top of the page for that endpoint to make things easy to find.

Error reporting

The result of each request can be determined in 2 ways.

First, check the HTTP result code. This resultcode will always be returned because it is part of the HTTP protocol and will tell you the initial result of your request.
For instance, a 200 OK code tells you that the request was correct as far as data, headers and authentication is concerned.

Second, check the Error or ErrorList in the reply for possible error codes. If you see no items in ErrorList (if defined in the reply) and an error code 0, then this means the request was completed without a problem.

If there is however an error, this means: the request was not completed, the data was not stored and the found issue is returned to you. If possible, all errors are returned at once in the ErrorList array.