code: function AGI(channel, command, commandId) {
    AGI.super_.call(this, 'AGI');
    this.set('Channel', channel);
    this.set('Command', command);
    this.set('CommandID', commandId);
  }
docs: AGI Action.
  @constructor
  @see Action(String)
  @see https://wiki.asterisk.org/wiki/display/AST/ManagerAction_AGI
  @param {String} Channel that is currently in Async AGI.
  @param {String} Application to execute.
  @param {String} This will be sent back in CommandID header of AsyncAGI exec event notification.
  @augments Action