Many times, a revert is accompanied by a message on the user's talk page. In the Notifications API, we'd like any relevant user talk page message IDs to be included with revert notifications.
Essentially, take the revert ID, use the Talk Page API (https://en.wikipedia.org/api/rest_v1/page/talk/User_talk:Jimbo) and see if any of the HTML snippets include the revert ID. If so, that talk page message's sha should be returned in the notification API as part of the revert notification object.