Skip to content
appsgit

Check

Check is an agent skill (a SKILL.md file) from JuliusBrussee/cavekit. Read-only drift detector. Diffs SPEC.md against current code and reports violations grouped by severity. It works with Claude Code and Codex and has 1,148 GitHub stars across a repository of 2 listed skills.

github.com/JuliusBrussee/cavekit/skills/check (opens in a new tab)

  • Multi-skill repo
  • Plugin marketplace
  • Security
  • Actively maintained
View on GitHub (opens in a new tab)

Add this skill

Claude

This repository is a Claude Code plugin marketplace. In Claude Code:

/plugin marketplace add JuliusBrussee/cavekit
/plugin install ck@cavekit-marketplace

In the Claude apps, zip the check folder and upload it under Customize > Skills > + > Upload a skill (code execution must be on).

ChatGPT / Codex

Codex reads skills from .agents/skills/ in a repo or ~/.agents/skills/ for every project:

git clone --depth 1 https://github.com/JuliusBrussee/cavekit.git
cp -r cavekit/skills/check .agents/skills/check   # repo; ~/.agents/skills for all projects

Standalone skills also load in the ChatGPT desktop app.

Cursor

Cursor loads skills from .cursor/skills/ (or ~/.cursor/skills/) and also reads .claude/skills/:

git clone --depth 1 https://github.com/JuliusBrussee/cavekit.git
cp -r cavekit/skills/check .cursor/skills/check   # project; ~/.cursor/skills for all projects

Source (checked Oct 7, 2026): code.claude.com/docs/en/skills (opens in a new tab), code.claude.com/docs/en/plugin-marketplaces (opens in a new tab), support.claude.com/en/articles/12512180-using-skills-in-claude (opens in a new tab), learn.chatgpt.com/docs/build-skills (opens in a new tab), cursor.com/docs/context/skills (opens in a new tab)

What this skill does

Read-only drift detector. Diffs SPEC.md against current code and reports violations grouped by severity. Writes nothing — suggests remedies via the spec or build skills but never invokes them. Triggers when the user asks to check drift, audit the spec, verify invariants, or ask whether code still matches the spec. Phrasings: "check drift", "audit the spec", "does the code still match §V", "check invariants", "spec vs code". Pure diagnostic. Reports violations. Writes nothing.

When it triggers

  • Triggers when the user asks to check drift, audit the spec, verify invariants, or ask whether code still matches the spec.
  • "check drift"
  • "audit the spec"
  • "does the code still match §V"
  • "check invariants"
  • "spec vs code"

More skills in JuliusBrussee/cavekit

2 skills are listed from this repository.

Similar skills

More security skills

All Security

FAQ

Check FAQ

Still curious? Email info@appsgit.com.

What is the Check skill?

Check is an agent skill (a SKILL.md file) from JuliusBrussee/cavekit. Read-only drift detector. Diffs SPEC.md against current code and reports violations grouped by severity. It works with Claude Code and Codex and has 1,148 GitHub stars across a repository of 2 listed skills. Its SKILL.md lives at github.com/JuliusBrussee/cavekit/skills/check.

How do I install the Check skill?

In Claude Code, run /plugin marketplace add JuliusBrussee/cavekit and then /plugin install ck@cavekit-marketplace. For Codex or Cursor, copy the check folder into .agents/skills/ or .cursor/skills/.

Is the Check skill free?

Yes. The repository is open source under the MIT license.

Is Check maintained?

The repository's most recent commit was on Aug 14, 2026. Its latest release is v3.1.0. appsgit only lists skills from repositories with a commit in the last six months.