Interesting...
I just got a follow request from #Awakari, with its own detailed and formatted message, and it never occurred to me that that's the sort of thing that #ActivityPub supports, though it does make sense.
I'm also a little surprised because my understanding has been that the main reason they are controversial is because they don't get permission to crawl people's profiles, but here they've sent a customized agreement type thing for me to look at...