Agent Session & Directory Forker

A small bash wrapper for running coding agents (codex, claude) across git worktrees. Spin up parallel agent sessions in isolated checkouts, fork worktrees with uncommitted changes intact, and generate handoff summaries for resuming later.

Install

Homebrew

brew install phelat/tap/asdf

When installed with Homebrew, upgrade with:

brew upgrade phelat/tap/asdf

Manual install

curl -fsSL https://raw.githubusercontent.com/PHELAT/asdf/main/install.sh | sh

The installer places asdf in ${ASDF_INSTALL_DIR:-$HOME/.local/bin} and sets up shell completion for zsh/bash automatically.

If another asdf command already exists on your PATH, the installer falls back to asdff and prints a warning. You can force a name with ASDF_INSTALL_NAME=asdf or ASDF_INSTALL_NAME=asdff.

Quick start

asdf                            # default agent in local checkout
asdf claude my-feature          # claude in worktree "my-feature"
asdf my-feature                 # default agent in "my-feature"
asdf my-feature cd              # shell into the worktree
asdf my-feature fork my-v2      # fork with uncommitted changes
asdf my-feature rm              # remove the worktree
asdf my-feature rm --force      # discard changes and remove the worktree
asdf my-feature wdid            # show/generate handoff summary
asdf list                       # list worktrees with dates and summaries
asdf update                     # self-update

Anything after -- is forwarded to the agent: asdf claude my-feature -- --dangerously-skip-permissions

Agents

Supported: codex, claude. If none is specified, asdf uses ASDF_DEFAULT_AGENT if set, then codex if installed, then claude.

Workspaces

• local — the current git checkout.
• Any other name — an existing worktree, or a new one created at ../<repo>-worktrees/<name>.

parent/
  my-repo/                  # primary checkout
  my-repo-worktrees/
    feature-a/
    feature-b/

Override the location with ASDF_WORKTREE_DIR.

Commands

Command	Description
(default)	Select a checkout and exec the agent.
wdid	Print the worktree's .wdid.md handoff summary (“What Did I Do”). Generates one via the agent if missing.
cd	Open an interactive shell in the selected checkout.
rm [--force]	Remove a named worktree. Use --force to discard modified or untracked files. The local, primary, and current checkouts are protected.
fork <new>	Create a new worktree from the current HEAD, copying staged, unstaged, and untracked files. Refuses to fork with unresolved merge conflicts.
list	List worktrees newest-first with creation dates and summaries.
update	Self-update from the upstream repository.
version	Print version.
help	Print usage.

When stdout is a terminal, wdid and list render Markdown with glow, mdcat, bat, or less (first found), falling back to plain text.

Shell completion

The installer sets up completion automatically. For manual setup:

# zsh
eval "$(asdf --completion zsh)"

# bash
eval "$(asdf --completion bash)"

Completes workspace names, agents, and commands.

jkl — Just Kickstart Locally ;)

An optional bash script that runs when asdf creates a new worktree (including via fork). Place a file named jkl at the repo root for setup tasks like copying .env files, symlinking node_modules, or running npm install.

Details and example

asdf looks for jkl in the new worktree first, then in the source checkout. For fork, it runs after uncommitted changes have been copied. If jkl exits non-zero, asdf aborts.

Environment variables passed to jkl:

Variable	Meaning
ASDF_JKL_FILE	Absolute path to the jkl file being executed.
ASDF_JKL_SOURCE_DIR	Source checkout or worktree.
ASDF_JKL_TARGET_DIR	The newly created worktree.
ASDF_JKL_WORKSPACE	The new worktree's name.

The working directory is set to ASDF_JKL_TARGET_DIR.

#!/usr/bin/env bash
set -euo pipefail

for f in .env .env.local .vscode/settings.json; do
  if [ -f "$ASDF_JKL_SOURCE_DIR/$f" ] && [ ! -e "$ASDF_JKL_TARGET_DIR/$f" ]; then
    mkdir -p "$(dirname "$ASDF_JKL_TARGET_DIR/$f")"
    cp "$ASDF_JKL_SOURCE_DIR/$f" "$ASDF_JKL_TARGET_DIR/$f"
  fi
done

if [ -d "$ASDF_JKL_SOURCE_DIR/node_modules" ] && [ ! -e "node_modules" ]; then
  ln -s "$ASDF_JKL_SOURCE_DIR/node_modules" node_modules
fi

echo "kickstart for $ASDF_JKL_WORKSPACE done"

Environment variables

Configuration reference

Variable	Default	Meaning
ASDF_DEFAULT_AGENT	codex if installed, else claude	Agent when none is given.
ASDF_DEFAULT_WORKSPACE	local	Workspace when none is given.
ASDF_WORKTREE_DIR	../<repo>-worktrees	Where new worktrees are created.
ASDF_UPDATE_CHECK	1	Set 0 to disable update warnings.
ASDF_ANALYTICS	1	Set 0 to disable anonymous analytics.
ASDF_INSTALL_DIR	$HOME/.local/bin	Installer destination directory.
ASDF_INSTALL_NAME	asdf (or asdff fallback)	Installer command name.

Requirements

• bash, git, awk, sed
• codex and/or claude on PATH
• Optional: glow, mdcat, or bat for rendered Markdown output