You can use Groove Agent independently of a host application.
If you use Groove Agent as a standalone application, an additional section is available at the top of the control panel. In this section, you can define key commands, set up audio and MIDI interface routings, adjust the master volume, and access the integrated MIDI scratch pad, which allows you to record your musical ideas without having to start a MIDI sequencer application. It can also be used to play multitrack arrangements that trigger the different programs.