Borrowing it
Nothing to install: this file belongs to lagz0ne/c3-skill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/lagz0ne/c3-skill/main/CLAUDE.mdgit clone --depth 1 https://github.com/lagz0ne/c3-skillWrote 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.
[](https://agentmods.dev/instructions/lagz0ne/c3-skill/claude-md)<a href="https://agentmods.dev/instructions/lagz0ne/c3-skill/claude-md"><img src="https://agentmods.dev/badge/instructions/lagz0ne/c3-skill/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.
<a href="https://agentmods.dev/instructions/lagz0ne/c3-skill/claude-md"><img src="https://agentmods.dev/badge/instructions/lagz0ne/c3-skill/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.01807 | $0.01807 |
| Opus 5.5 | $0.00723 | $0.00723 |
| Sonnet 5.5 | $0.00361 | $0.00361 |
| Haiku 4.5 | $0.00181 | $0.00181 |
Grade A, and why
c3-skill 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 2mo 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.
How it starts
The opening of the file, as written. The whole thing — 132 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Working in this repo
This is the C3 product source — the Go CLI and the Claude skill that ships it. This file is the repo-dev contract: how to invoke C3 here, how we work, and how we release. It teaches no product behavior.
What C3 is, the operation set, and the change-unit / freeze / canvas model are owned by skills/c3/SKILL.md. Read it there; do not duplicate it here.
Local C3 Source Rule
This repository is the C3 project source. Work here is intentionally outside the installed/global C3 skill scope — never let the global skill answer for this checkout.
Hard rules:
- Do not use bare
c3x; it may resolve to the global installed skill. - Do not load C3 from
~/.agents/skills/c3,~/.claude/skills/c3,~/.codex/skills/c3, or marketplace installs for this repo. - Load C3 skill instructions from
skills/c3/SKILL.mdin this checkout. - Run C3 through the local built wrapper:
C3X_MODE=agent bash skills/c3/bin/c3x.sh <command>. - If
skills/c3/bin/c3x.shor the matching local binary is missing, tell the user — CI builds binaries, not you. Only runbash scripts/build.shwhen explicitly debugging the build. - The wrapper rebuilds only when the platform binary is absent; after editing CLI source, delete the stale gitignored binary in
skills/c3/bin/so you don't dogfood old code. - At session start, create a local alias/function and use it for every C3 command:
alias c3local='C3X_MODE=agent bash skills/c3/bin/c3x.sh'
c3local check
If C3 output looks wrong, commands fail unexpectedly, or behavior differs from source changes, suspect the wrong C3 version is being used. Prove the path/version before continuing.
File lookup: c3local lookup <file-or-glob> maps files/directories to components + refs.
CLI: c3local <command> after the alias above; see skills/c3/SKILL.md for the operation set.
Workflow
- Load
/superpowers:brainstormingand/superpowers-developing-for-claude-code:developing-claude-code-pluginsup front. - Use
AskUserQuestionToolwhere possible — it yields a better-grounded answer. - Start with brainstorming to pin the intention; align the concept in prose before offering implementation menus.
- Once understood, write the plan, then implement in parallel using subagents.
- Before claiming work is done: run
/noslopto strip AI slop, then run the local C3 flow (c3local checkfor doc integrity +c3local evalfor fact↔code conformance) to verify docs match code. - Delegate to
/releasewhen done; confirm scope with the user. Patch by default.
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.
- 2mo ago First seen · 132 lines · 1,807 tokens per session scan A 3ddbc2bdf31a
c3-skill CLAUDE.md is an instructions file published in the GitHub repository lagz0ne/c3-skill (12 stars, last pushed 3mo ago), licensed MIT. It adds 1,807 tokens to every session, about $0.0072 per session on Opus 5.5. 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 2026-08-30.
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