This module is designed for web-developer/ops. Using Incoming WebHooks to send messages to slack for notifying. It's very easy to set notifier in follow steps:
Inbox is the communications hub for ELMSLN. It is an authority based distribution meant to be a messaging and communications center. All other distributions wishing to interface w/ the student's "inbox" can use the API capabilities to send messages to the student (or any other user for that matter).
This makes the most sense when in ELMSLN but as per the methodology can, and should be able to be stood up on its own as a communications hub for other projects (though educational focused most likely).