The actions in the hooks configuration could live in any route, but some actions are already available in eox-hooks, and there are:
post_to_webhook_url: Send data to a webhook url specified in the hook settings.trigger_enrollments_creation: starts an async task that enrolls a user in a list of courses.trigger_grades_assignment: propagates grades to a course component.
For more information, you can see the code in actions.py.