The on-premises install of the Enterprise version of Veracity Learning includes a system level API for creating users and LRSs.
This API works exactly as the LRS level does, with the same conventions for GET, PUT, POST and DELETE. You'll find the API Key management page under the admin tools when logged in as the administrator. While the terminology is similar, don't confuse the admin API with the LRS level APIs. The Admin API is for managing the entire installation, not an individual LRS.