Running some tests tonight, and every second or third request to the DataManager API is returning the HTML for https://developer.mapquest.com/documentation/ instead of the expected JSON. Since I can literally send the same request several times in a row and see this behavior, this seems to be a problem on the MapQuest side, rather than a defective request payload.
Is there something going on with the API?
I see a forum post from 2015 that says, "We do not offer an endpoint, however, we are working on an API Status Page that allows users to sign up for e-mail notifications so that they can be notified when the operational status of an API changes." A response from 2018 says that there is still no status page. Has there been any progress in this area? Any way to find out about outages, or even to notify MapQuest when something is going on (other than posting here)?