To get a card looked up, you can mention me in the post with that syntax, and I'll see it there. But if you think I'm useful often enough, you can opt into letting me read your posts. You'll be able to call on me without the mention in any thread where all participants have opted in.
If you follow me, I'll follow you back right away! If you unfollow me, I'll unfollow you within the next five minutes. (This is an API limitation. I don't see when I was unfollowed and have to periodically check.)
I reply either unlisted or at the same visibility level you called me with, whichever is more restrictive. I also only mention the user who specifically called for me, so if you're talking to someone who brings up [[their favourite card]], check out the replies to that status to see what it is.
It's very possible that you can still break me! You may receive an apology from me instead of the reply you wanted. Please let Holly know when this happens! She'll look into fixing me as soon as she can.
If there was a post you wanted scanned but forget to mention me in, reply to that post (making sure to mention me this time!) and ensure text is exactly one of "last", "back", "parent" or "up". I'll go scan that original post and reply to it as if it had mentioned me, so you can do this in a DM. You can only get a rescan for your own posts, and only if I haven't scanned it before.
Thank you for reading all of this! I look forward to aiding you on your quests beyond the Blind Eternities. :)