Thanks for remembering to add this here, forgot to mention it. Two minor wording nitpicks here.

I think I've used the word instance everywhere so far, so I'd like to try to stay a bit consistent there :) so instance rather than value.

Also, ideally I'd have a separate instance here for reference resolvers and this new thing but being that they're both really simple I was lazy, so you did the right thing, but I'd like to eventually formally document these separately, so rather than " returns True if..." just say " that checks..."