EDA Rulebooks and post_events.. use cases? examples?

Howdy, I’m looking for some assistance in understanding how to use post_events and perhaps why? The description for that states:

The artifacts from the workflow template execution are inserted back into the rule set as events

So… artifact being variables, facts, perhaps stats? Does this mean artifacts are sent back to the rulebook from the playbook?
Meaning you could perhaps respond to the webhook source with artifact data?

Im just having trouble understanding or visualizing… what you’d use that for and how.
Many thanks!