How to determine available @Managed Types

This may be a very stupid question but how do I find out what @Managed Types are available for the new Model configuration?

I see lots of references to ModelMap<Task> and notes that org.gradle.api.Task implements ModelMap but I don’t see that relationship in the documentation for 2.11.

I’m naively trying to write a RuleSource plugin that appends a new Ivy repository to the Repositories collection. I’ve tried various configurations such as:
ModelMap<ArtifactRepository>, ArtifactRepositoryCollection etc. For each attempt I get a similar error message:

        - <no path> ArtifactRepository (parameter 1) [*]

Is Task the only interface that has been migrated to a Managed type at the moment?

Thanks for any advice!