A ready-made invite in your words. Tweak it, then send. It goes out from you, and guests reply to you.
Example data. This is the list once guests start booking their own tents.
You get a page like this one to watch it fill up, invite everyone from your own names and tell us where the tents go. We pitch them before your guests arrive and pack down the morning after. Send us your date and venue and we'll come back with what we can do.