pi-subagent-windows0.1.2

Pi Subagent for Windows (no tmux)

Hidden, persistent Pi subagents for independent reviews, investigations, and delegated implementation — without tmux.

This is a Windows port of badlogic/pi-subagent. The agent-facing workflow is unchanged: the main Pi agent spawns named subagents with the subagent CLI, waits for their final reports, steers them when needed, and stops them when done. Everything happens in the background — there is no attach screen.

How it works

Upstream runs each subagent inside a tmux session and lets a human attach to its live TUI. Windows has no tmux, so this port replaces the tmux layer with a hidden process host:

• Each subagent is a detached, hidden supervisor process that owns a pi --mode rpc child.
• The supervisor holds the child's stdin pipe, drains its protocol output, writes supervisor.log, and auto-cancels extension dialogs (there is no interactive screen to answer them).
• Runs are tracked by pid, stopped with taskkill /T /F, and survive parent /reload, session switches, and parent crashes.
• Subagents are status-only on Windows. Use subagent status, subagent wait, and the run's session.jsonl for inspection.

On non-Windows platforms the upstream tmux behavior is kept, so the fork stays mergeable with upstream.

Requirements

• Pi
• Node.js 22.19 or newer
• Windows (no tmux required)

Install

pi install npm:pi-subagent-windows

Or install straight from GitHub:

pi install git:github.com/muntasimulhaque/pi-subagent-windows

Or clone it manually into Pi's global extension directory:

git clone https://github.com/muntasimulhaque/pi-subagent-windows.git ~/.pi/agent/extensions/pi-subagent-windows

Run /reload in an existing Pi session (or start a new one). On Windows the extension writes subagent.cmd and an extensionless subagent sh shim into ~/.pi/agent/bin, so the CLI is on PATH from both PowerShell/cmd and Git Bash.

Usage

Spawn with a descriptive name using the parent session's provider, model, and thinking level:

subagent spawn --name review --prompt "Review the current diff independently"

Override the model configuration when needed:

subagent spawn \
  --provider commandcode \
  --model deepseek/deepseek-v4.1-flash \
  --thinking low \
  --prompt "Find the relevant implementation"

Provide multiple prompt fragments and files:

subagent spawn \
  --file /tmp/spec.md \
  --prompt "Implement this specification" \
  --prompt "Run the targeted tests"

Restrict tools for a read-only investigation:

subagent spawn --tools read,grep,find,ls --prompt "Investigate the failure"

Manage a run by its generated handle:

subagent status a1b2c3
subagent rename a1b2c3 "error handling review"
subagent send a1b2c3 "Focus on error handling"
subagent send a1b2c3 --follow-up "Then summarize"
subagent wait a1b2c3
subagent stop a1b2c3
subagent list

Run /subagent to list active subagents spawned by the current session. On Windows, selecting one shows its status and session file.

Run files

Each run lives in ~/.pi/agent/subagents/<handle>/:

File	Purpose
metadata.json	State, model, session pointers
session.jsonl	The child Pi session (full transcript)
inbox/	Queued messages (steering, follow-ups)
supervisor.log	Process host log, child stderr, auto-cancelled dialogs
supervisor.pid	Process tracking

Differences and limitations

• No attach screen. Subagents are observable through status, wait, and the session file, not a live TUI.
• --file handling: text file contents (up to 1 MB) are inlined into the first prompt; larger or binary files are referenced by path and can be read by the subagent's read tool.
• Extension dialogs (select, confirm, input, editor) are auto-cancelled inside hidden subagents, with a note in supervisor.log. Fire-and-forget notifications are ignored.
• Suspension kills the current turn. Resuming relaunches the run idle with its full history.
• Nested subagents remain disabled.

Credits

Forked from badlogic/pi-subagent by Mario Zechner (MIT). See LICENSE.