fork

A pi extension that spawns subagents as separate pi sessions in tmux windows.

Requirements

• tmux
• Run pi inside tmux

Install

pi install git:github.com/johan/fork

Or try without installing:

pi -e git:github.com/johan/fork

How it works

The LLM gets one tool: spawn. Calling it opens a new tmux window running pi with the given task and returns immediately. When the child finishes, its final message is sent back over a Unix socket and delivered as a notification that triggers a new turn.

Use tmux keybindings (Ctrl+B n/p/1-9, etc.) to navigate between windows.

If you take over a subagent's tmux window (by typing or pressing Esc), it stays alive as a regular interactive pi session — it won't send results back.