groundwork: Instructions file for Claude Code

CLAUDE.md

groundwork CLAUDE.md is an instructions file for Claude Code from etr/groundwork. It costs 2,829 tokens per session, scanned A, a copy of groundwork AGENTS.md, MIT.

A project instruction file for Groundwork, a Claude Code plugin containing reusable development instructions called skills. It explains the project’s structure and how those skills are created and used.

In plain words
What is it for?
Use it when changing Groundwork’s skills, documentation, project structure, or installation process.
Why use it?
It gives the coding agent the context needed to work consistently on the plugin and follow its documented conventions.

Instructions file for Claude Code

Written for Claude Code: ${CLAUDE_PLUGIN_ROOT} variable. Also seen: reads .claude/ paths; mentions .claude-plugin; mentions CLAUDE.md.

This is etr/groundwork's own configuration. It tells Claude Code how to work on groundwork 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 groundwork configures →

Runs only inside a plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else, and the catalogue could not identify which plugin ships it.

Reuse

Borrowing it

Nothing to install: this file belongs to etr/groundwork. 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/etr/groundwork/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/etr/groundwork

Made for: Claude Code.

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Per session 2,829 This file is loaded in full into every session.
When invoked 2,829 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 97% copy Near-identical to another mod 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 $0.02829 $0.02829
Opus 5.5 $0.01132 $0.01132
Sonnet 5.5 $0.00566 $0.00566
Haiku 4.5 $0.00283 $0.00283

Measured 1mo ago against content hash 366ba1aa2941, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

groundwork 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 1mo 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.

Origin

This is a copy

97% identical to groundwork AGENTS.md — 10 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

CLAUDE.md · 151 lines

How it starts

The opening of the file, as written. The whole thing — 151 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

Groundwork is a Claude Code plugin that provides a skills library for structured development workflows. It contains 40 skills spanning the full lifecycle — discovery, domain modeling, architecture, planning, TDD, debugging, validation, and shipping. Every capability is a skill; there is no separate commands layer (skills are both user-invocable via /groundwork:<name> and, where appropriate, model-invocable).

The using-groundwork skill is the lifecycle router: it maps work → skill across every phase and is the only way the model can surface user-only leaves (which are invisible to it at call time). When authoring or editing a skill, see docs/developing-skills.md (contributor guide: anatomy, frontmatter, tier selection, authoring discipline, progressive disclosure).

Project Structure

This is a Claude Code plugin, not a traditional software project. There is no build step for Claude Code use. A separate installer (install-skills.sh) exports the skills to other AI coding harnesses (see "Multi-target installation" below).

groundwork/
├── .claude-plugin/plugin.json  # Plugin manifest
├── skills/                     # Markdown-based workflow skills (SKILL.md files) — the only entry-point layer
├── agents/                     # Subagent definitions (AGENT.md files)
├── hooks/                      # Event-driven automation (SessionStart, PostToolUse, SubagentStop, PreCompact)
├── lib/                        # JavaScript utilities (+ co-located *.test.js)
├── references/                 # Runtime reference files loaded by skills/agents
│   ├── checklists/             # Shared checklists read by BOTH a producer skill and a reviewer agent (testing: test-driven-development ↔ test-quality-reviewer; accessibility: ux-design ↔ design-consistency-checker)
│   └── engineering-principles.md  # Named-principle vocabulary (deep modules, Hyrum's Law, Chesterton's Fence, …)
├── tests/                      # Node test suites; run via tests/run-tests.sh
├── docs/                       # User-facing documentation
├── install-skills.sh           # Multi-target export installer (Codex, OpenCode, Kiro, Pi, ZCode)
├── install-config.txt          # Export exceptions (drops + renames); fail-closed by default
├── build-zcode-marketplace.sh  # Packages the --zcode-plugin export as a ZCode marketplace (dist/, gitignored)
└── pi-extension/               # Pre-built TypeScript extension copied into Pi installs

Read the full file on GitHub · 151 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. 1mo ago Changed · +4 lines · +298 tokens per session 366ba1aa2941
  2. 1mo ago Changed · +9 lines · +278 tokens per session 4789fbcb2737
  3. 1mo ago Changed · +4 lines · +305 tokens per session 61c5d3af7015
  4. 1mo ago First seen · 134 lines · 1,948 tokens per session scan A f5650a81a204

Subscribe to this mod's changes

groundwork CLAUDE.md is an instructions file published in the GitHub repository etr/groundwork (44 stars, last pushed yesterday), licensed MIT. It adds 2,829 tokens to every session, about $0.0113 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 97% identical to groundwork AGENTS.md, differing in 10 lines, and is treated as a copy.

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