A minimal CLI for installing agent skills. Symlink-only, lockfile-driven.

skillfu gives your agents new capabilities instantly — like Neo in The Matrix who instantly learns kung fu after downloading the program, skillfu instantly equips your agents with new skills.

It's a focused replacement for the Vercel skills CLI — it does one thing well: install, track, and update skills via symlinks with a lockfile as the source of truth.

# npm
npm install -g @mcowger/skillfu

# From source
git clone <repo-url> skillfu && cd skillfu
bun install
bun run build

Install skills from a GitHub repo or local path.

# Install all skills from a repo (global)
skillfu add vercel-labs/agent-skills

# Install specific skill (positional arg)
skillfu add vercel-labs/agent-skills github-actions-docs

# Install specific skills
skillfu add vercel-labs/agent-skills --skill frontend-design --skill skill-creator

# Install to project directory (local scope)
skillfu add vercel-labs/agent-skills --skill frontend-design -l

# Install from a local path
skillfu add ./my-skills

# Install from a specific branch
skillfu add vercel-labs/agent-skills --ref develop --skill frontend-design

# Shorthand: @skill-name filter
skillfu add vercel-labs/agent-skills@frontend-design

# Shorthand: #branch reference
skillfu add vercel-labs/agent-skills#develop

Remove installed skills.

skillfu remove frontend-design
skillfu remove frontend-design skill-creator
skillfu remove frontend-design -l    # from project scope
skillfu remove frontend-design -y    # skip confirmation

Ensure installed skills match the lockfile. Idempotent — safe to run repeatedly (like npm ci).

skillfu install       # restore global skills from lockfile
skillfu install -l    # restore project skills from lockfile

This is the primary command for:

• Setting up a new machine after cloning a repo (with .agents/skills.lock committed)
• Recovering from accidentally deleted symlinks
• CI/CD environments
• Removing orphaned skills not tracked in the lockfile

Check for and install updated versions of skills.

skillfu update                          # update all global skills
skillfu update -l                       # update all project skills
skillfu update --skill frontend-design   # update a specific skill

Update detection uses the skills.sh API for hash comparison, falling back to the GitHub Trees API when unavailable. Local path skills cannot be updated remotely.

Output shell completion script.

# bash
skillfu completions bash > ~/.local/share/bash-completion/completions/skillfu

# zsh
skillfu completions zsh > ~/.zfunc/_skillfu

# fish
skillfu completions fish > ~/.config/fish/completions/skillfu.fish

~/.config/skillfu/
├── skills.lock                                 # Lockfile
└── skills/                                      # Canonical skill files
    └── frontend-design/
        └── SKILL.md

~/.agents/skills/                                # Symlinks (where agents look)
└── frontend-design → ~/.config/skillfu/skills/frontend-design/

<project>/
├── .agents/
│   ├── skills.lock                              # Project lockfile (commit this!)
│   └── skills/                                  # Skill files (no symlinks needed)
│       └── frontend-design/
│           └── SKILL.md

Any agent that reads from ~/.agents/skills/ (global) or .agents/skills/ (local) picks up installed skills automatically — no agent-specific configuration needed.

Skills are tracked in a lockfile that serves as the source of truth:

• Global: ~/.config/skillfu/skills.lock
• Project: .agents/skills.lock

The project lockfile is designed to be committed to version control. Skills are sorted alphabetically and timestamps are omitted to minimize merge conflicts — two branches adding different skills produce non-overlapping JSON keys that git can auto-merge.

Agent skills are reusable instruction sets that extend your coding agent's capabilities. They're defined in SKILL.md files with YAML frontmatter:

---
name: my-skill
description: What this skill does and when to use it
---

# My Skill

Instructions for the agent to follow when this skill is activated.

Discover more skills at skills.sh.

bun install          # Install dependencies
bun run dev add ...  # Run locally
bun test             # Run tests
bun run build        # Compile to dist/skillfu