Uh, are you sure you did? I mean it's just using the hooks API of Claude code to play a sound via the terminal itself?
Heck, they even outlined it in the readme
> peon.sh is a Claude Code hook registered for SessionStart, UserPromptSubmit, Stop, and Notification events. On each event it maps to a sound category, picks a random voice line (avoiding repeats), plays it via afplay (macOS) or PowerShell MediaPlayer (WSL2), and updates your Terminal tab title.
Looking at the install script and peon.sh does not raise any over engineering flags for me. It's as simple as the functionally makes it necessary