goInstant crash

var url = 'https://goinstant.net/56231ff9e929/mouseghost';
var sessions;
var room; var connection = new goinstant.Connection(url);
  connection.connect(function (err) {
    if (err) return;
    room = connection.room('localhost');
    room.join(function(err) {
      if (err) throw err;
      sessions = room.key('sessions');
      });
    });

sessions.get(function(){console.log(arguments)})