code: function idletime(req, res) {
    var obj = req.db.getRawKey(req.args[0], req)
      , diff;
    if(obj === undefined) return res.send(null, null);
    diff = Date.now() - obj.t;
    diff = Math.round(diff / 1000);
    res.send(null, diff);
  }
docs: Respond to the IDLETIME subcommand.