repo-hygiene: Instructions file for Claude Code

CLAUDE.md

repo-hygiene CLAUDE.md is an instructions file for Claude Code from gg-mo/repo-hygiene. It costs 710 tokens per session, scanned A, original, MIT.

A set of instructions for keeping a code repository orderly while a coding agent changes it. It covers orienting before edits, documenting code, updating public documentation, testing, and checking work before committing.

In plain words
What is it for?
Use it to guide repository cleanup, documentation updates, testing, verification, and the development of agent skills.
Why use it?
It reduces common maintenance problems such as undocumented changes, untested code, and commits made without verification. It also defines how the included instructions should be tested and improved.

Instructions file for Claude Code

Written for Claude Code: SessionStart hook event. Also seen: mentions subagents; mentions Claude Code; mentions Codex.

This is gg-mo/repo-hygiene's own configuration. It tells Claude Code how to work on repo-hygiene itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything repo-hygiene configures →

Reuse

Borrowing it

Nothing to install: this file belongs to gg-mo/repo-hygiene. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/gg-mo/repo-hygiene/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/gg-mo/repo-hygiene

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for repo-hygiene CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/gg-mo/repo-hygiene/claude-md/github.svg)](https://agentmods.dev/instructions/gg-mo/repo-hygiene/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/gg-mo/repo-hygiene/claude-md"><img src="https://agentmods.dev/badge/instructions/gg-mo/repo-hygiene/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for repo-hygiene CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/gg-mo/repo-hygiene/claude-md"><img src="https://agentmods.dev/badge/instructions/gg-mo/repo-hygiene/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 710 This file is loaded in full into every session.
When invoked 710 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00710 $0.00710
Opus 5 $0.00355 $0.00355
Sonnet 5 $0.00142 $0.00142
Haiku 4.5 $0.00071 $0.00071

Measured 10d ago against content hash 7ae06930b0dd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

repo-hygiene CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 64 lines

How it starts

The opening of the file, as written. The whole thing — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Repo Hygiene — Contributor Guidelines

What this plugin is

repo-hygiene is a small, opinionated skill set that keeps codebases healthy as coding agents work in them. It complements (does not replace) superpowers. Where superpowers provides workflow disciplines (brainstorming, TDD, debugging, planning), this plugin provides the lower-level hygiene that should hold across every change:

  • Orient before you edit
  • Docstring what you write
  • Update docs when you change public surface
  • Test what you ship
  • Verify before you commit

Each skill is a separate file under skills/<name>/SKILL.md. The bootstrap (using-repo-hygiene) is injected at session start via the hooks/session-start hook on every supported harness.

If you're editing a skill

Skills are documentation that shapes agent behavior. Edits should be tested, not just written:

  1. RED — baseline test. Dispatch a subagent with a representative scenario WITHOUT the skill loaded. Document what it does naturally.
  2. GREEN — write the skill. Address the specific failure modes you saw.
  3. REFACTOR — close loopholes. Dispatch again WITH the skill, look for rationalizations, plug them.

Don't commit edits to skills that weren't tested. See superpowers:writing-skills for the full methodology.

What does NOT belong in this plugin

  • Skills tied to a specific language, framework, or product. Those go in their own plugin.
  • Anything superpowers already does well. Don't reinvent TDD, brainstorming, or planning.
  • Hard rules that should be linter / CI checks. If a regex can enforce it, it doesn't need a skill.
  • Personal preferences. Skills should generalize across users.

Plugin / platform plumbing

Platform Manifest
Claude Code .claude-plugin/plugin.json + .claude-plugin/marketplace.json
Codex (CLI + App) .codex-plugin/plugin.json
Cursor .cursor-plugin/plugin.json + hooks/hooks-cursor.json
OpenCode .opencode/plugins/repo-hygiene.js + package.json main field
Gemini CLI gemini-extension.json + GEMINI.md
Copilot CLI Reuses hooks/ (detects COPILOT_CLI=1 env var)

Read the full file on GitHub · 64 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 64 lines · 710 tokens per session scan A 7ae06930b0dd

Subscribe to this mod's changes

repo-hygiene CLAUDE.md is an instructions file published in the GitHub repository gg-mo/repo-hygiene (3 stars, last pushed 4mo ago), licensed MIT. It adds 710 tokens to every session, about $0.0036 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other instructions, from other repositories

next.js AGENTS.md

AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

vercel/next.js · 7,296 tokens

codex AGENTS.md

AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

openai/codex · 5,153 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens

vscode oss-third-party-notices.instructions.md

Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).

microsoft/vscode · 5,001 tokens

langchain AGENTS.md

AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.

langchain-ai/langchain · 4,469 tokens