code: function(){
  
    var rl = readline.createInterface(process.stdin, process.stdout, completer);
    var prefix = bold('prey>') + ' ';
    var prefix_length = 6;
  
    rl.on('line', function(line) {
      line = line.trim();
  
      if(line === 'quit' || line === 'exit')
        return rl.close();
  
      if (line !== '')
        handle_input(agent.commands.parse(line));
  
      rl.setPrompt(prefix, prefix_length);
      rl.prompt();
    });
  
    rl.on('close', stop);
  
    setTimeout(function() {
      console.log('\nWelcome back, master. Type "help" for assistance.\n');
  
      rl.setPrompt(prefix, prefix_length);
      rl.prompt();
    }, 300);
  
    return rl;
  
  }
docs: ////////////////////////////////////////////////////////////////// load //////////////////////////////////////////////////////////////////