Now I know it, but two things to observe:
I believe, there is an usability issue on the metrics table here:
The columns showing the type of response and if it goes by default are hidden, and you need to scroll the table horizontally. BUT, the scroll bar is in the very bottom of this long table, making it very hard to "discover" this data.
And you sum that issue with this information given by your staff:
"We do not provide a list of default metrics. That decision because we
want to encourage developers to fetch the metrics that are useful to
them, not just a generic long list of metrics."
And you see how confused I was.
But now it is all clear.