Your comments

I would like to add a trigger to send a notification when any guest in a given group or with a specific tag has connected.

Use: I have 18 machines that are not online very often, but need to have a manual Automate Version update (or other script) applied... if I have a tag, for example "Notify when online" that my techs can apply to multiple sessions, they get a notification when one of those machines connect, so that they can take the appropriate action before it again disconnects for another extended period of time.