skillzero

Modern agent harnesses expose every installed skill's name and description to the model (but not their full content). With many skills, that can still consume tokens, increase cost and add irrelevant context. Experts like Matt Pocock, Addy Osmani and swyx have called out the same problem.

skillzero solves it by diving skills into 3 categories:

1. Unmanaged: Skills that are untouched by skillzero - agents see their name and description as usual.

2. 👻 Hidden: Skills become completely hidden from the agent, but are still manually invokable (like commands).

3. 📚 Collection: Skills in collections are hidden by default, but become discoverable generated collection skills. This allows you to group skills for design, writing, etc. where the agent can invoke the skills when working on topics related to the collection.

Installation

npx skillzero # npm

pnpx skillzero # pnpm

yarn dlx skillzero # yarn

aube dlx skillzero # aube

Usage

# configure or sync global skills
skillzero ~/.agents/skills
# configure or sync project skills
skillzero .
# auto-detect the project or global roots and configure/sync them
skillzero

# update via Vercel's `skills` CLI, then apply skillzero settings again
skillzero update

# edit collections
skillzero collections

# undo all changes done by skillzero
skillzero undo
# undo the undo
skillzero redo

skillzero update requires Vercel's skills CLI to be available on PATH. Arguments after skillzero update are forwarded to skills update, including --global, --project, and --yes.

How

| Metadata | What skillzero changes | | --- | --- | | SKILL.md | Sets disable-model-invocation: true. | | agents/openai.yaml | Sets policy.allow_implicit_invocation: false |

Skills are hidden by setting the metadata needed to hide them from the Cursor/Claude Code harness and to hide them from Codex by setting the policy.

skillzero also stores its managed state and generated collection skills in a skillzero/ directory inside each skills root. skillzero --dry-run previews changes without writing. skillzero undo restores the metadata and removes generated collection changes; skillzero redo reapplies the most recently undone state.

Good Uses

Use skillzero for skills you want available but do not need on most tasks, like:

• one-off platform guidance
• migration guides
• niche framework rules
• experimental skills you are trying out
• skills that work like commands (you only invoke manually 99% of the time ... and some authors haven't heard of disable-model-invocation: true / the Codex policy yet)
• spreadsheet and document tools

Collections are great when you have multiple skills for one topic (e.g. for marketing, design, writing, ...) so the model can use them through the description.

Don't pick skills you use frequently, like:

• repo coding rules
• accessibility rules for a frontend project
• the framework guidance you use every day
• project-specific review or test placement rules
• accessibility related skills

Development

This project uses the package manager Aube.

aube install
aube run build

Run checks:

aube run typecheck
aube test
aube run test:package

Good to know

• Run /checkup to clean up unused skills.
• More tips in Matt Pocock's article on how to remove context bloat (/context, remove bundled skills, ...)