hey, is it kosher to post an open-core thing (part of codebase licensed AGPL and part licensed commercially, in my case) in #announcements?
If it's your project and it's Clojure/Script, yes. Presumably the AGPL part is open source and you plan to post a link to the project/source?
yes and yes
actually currently the AGPL part is 100% of the project but the license reserves the right to make it not 100%