Documentation for com.atlassian.confluence.plugins.createcontent.api.events?

In mining the source code for the Team Space Blueprint, there is a reference to the SpaceBlueprintHomePageCreateEvent. The implementation seems inconsistent as annotation seems to be the preferred way to write listeners, but the Team Space uses both the annotation and listener approaches. I'd like to be consistent. I'm also cautious as there are clear warning on https://developer.atlassian.com/confdev/confluence-plugin-guide/confluence-blueprints/custom-actions-with-the-blueprint-api "Deprecation Warning
The AbstractCreateBlueprintPageAction is no longer being used internally and is slated for removal in a future release. Please let us know via the Feedback form if your plugin currently extends this action, or if you plan to extend it." and I want to make sure I'm triggering off the recommended event but there is NO DOCUMENTATION on how this should be done. In fact, the only reference I can find of the SpaceBlueprintHomePageCreateEvent is in the Team Space Blueprint source code.
Can you please provide the documentation for the createcontent api?