pi-mono/packages/coding-agent/docs/windows.md

Windows Setup

Pi requires a bash shell on Windows. Checked locations (in order):

1. Custom path from ~/.pi/agent/settings.json
2. Git Bash (C:\Program Files\Git\bin\bash.exe)
3. Managed Portable Git Bash (~/.pi/agent/bin/portable-git/bin/bash.exe)
4. bash.exe on PATH (Cygwin, MSYS2, WSL)

If no bash is found, Pi downloads Git for Windows Portable Git into ~/.pi/agent/bin/portable-git. Set PI_OFFLINE=1 to disable automatic downloads.

Custom Shell Path

{
  "shellPath": "C:\\cygwin64\\bin\\bash.exe"
}