Requesting an exit to another character’s room - either through the UI or the command line - results in an exit that works once accepted but which does not show up. In this situation, list exits says This room has no exits.
A room exhibiting this is my stall at the Blackhoof Stables with exits back, stable, stables.
Perhaps an unintended side-effect of inactive exits - they’re hidden, but active?
Also, as mentioned in another thread, get exit gives Access denied, even for room owners (in theory it should work for everyone). list exits works but doesn’t give the exit IDs; scripts therefore have to use a keyword to select an exit.