>>20217
It does seem there is an rss feed available at https://endchan.net/agatha2/index.rss
However, this feed appears to only give notifications for the creation of new threads. And also I can't get even that to work consistently. So, not very useful as it stands. But you can try it.
It would be nice if there was some way to get notifications for all posts made on the board, but I don't think there is any way to do that currently.