We ship a SQL engine that also connects to REST services of Mendix. For many occasions, it is necessary to determine with what credential (log on code, maybe even user name) a user is logged on. However, sometimes the original log in credentials are not available, for instance when user is externally authenticated. In same way, it would be handy to retrieve the preferred user interface language.
Platforms such as Salesforce, Exact Online or Teamleader provide a standardized end point for this which is always at a specific location.
Of course, you can ask every Mendix app to put this data somewhere, but the costs are high and the turnaround time is a waste of days.
In similar way, such an endpoint makes it possible to validate that the REST service connected to is indeed powered by mendix.