claude-howto: Instructions file for Claude Code

CLAUDE.md

claude-howto CLAUDE.md is an instructions file for Claude Code from luongnv89/claude-howto. It costs 883 tokens per session, scanned A, original, MIT.

A set of instructions for Claude Code in a tutorial repository whose lessons are written as numbered Markdown modules and built into an EPUB, a digital book format.

In plain words
What is it for?
Use it when editing the tutorial, running documentation checks, testing Python scripts, formatting and type-checking code, checking security, or building the EPUB.
Why use it?
It gives the coding agent the repository's commands, file structure, writing rules, and checks so its edits fit the project and pass its quality gate.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md.

This is luongnv89/claude-howto's own configuration. It tells Claude Code how to work on claude-howto 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 claude-howto configures →

About the project

luongnv89/claude-howto is a visual, example-based guide to Claude Code, a coding tool that supports agents, hooks, skills, slash commands, and MCP servers. Developers use it to learn Claude Code through practical workflows and copyable templates, including the commands, agents, skills, plugins, and instructions catalogued here.

luongnv89/claude-howto · 41,418 stars · on GitHub · luongnv.com

Reuse

Borrowing it

Nothing to install: this file belongs to luongnv89/claude-howto. 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/luongnv89/claude-howto/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/luongnv89/claude-howto

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 claude-howto CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/luongnv89/claude-howto/claude-md/github.svg)](https://agentmods.dev/instructions/luongnv89/claude-howto/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/luongnv89/claude-howto/claude-md"><img src="https://agentmods.dev/badge/instructions/luongnv89/claude-howto/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 claude-howto CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/luongnv89/claude-howto/claude-md"><img src="https://agentmods.dev/badge/instructions/luongnv89/claude-howto/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 883 This file is loaded in full into every session.
When invoked 883 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 $0.00883 $0.00883
Opus 5 $0.00441 $0.00441
Sonnet 5 $0.00177 $0.00177
Haiku 4.5 $0.00088 $0.00088

Measured 10d ago against content hash 035a4879fe9b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

claude-howto 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 · 63 lines

How it starts

The opening of the file, as written. The whole thing — 63 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

Tutorial repo. Output is markdown in numbered modules 01- through 10-, not an app. Scripts in scripts/ exist only to validate docs and build the EPUB.

See also .claude/CLAUDE.md for stack/commands and STYLE_GUIDE.md for lesson structure.

Critical commands

# Quality gate (also runs on commit via pre-commit hooks)
pre-commit run --all-files

# Tests
pytest scripts/tests/ -v

# EPUB build (renders Mermaid with the local mmdc CLI — no network, needs mmdc on PATH)
uv run scripts/build_epub.py

# Python tooling
ruff check scripts/ && ruff format scripts/
mypy scripts/ --ignore-missing-imports
bandit -c scripts/pyproject.toml -r scripts/ --exclude scripts/tests/

Pre-commit runs 5 doc checks on .md changes: markdown-lint, cross-references, mermaid-syntax, link-check, markdown-rendering. All must pass. The EPUB build is not a pre-commit hook — it runs in CI only (build-epub job in .github/workflows/test.yml), because it needs a local mmdc binary that has no working arm64 build.

Architecture map

  • 01-10- — tutorial modules. Numbered prefix = learning order, not alphabetical. Do not reorganize.
  • Each module: README.md + copy-paste templates (.md, .json, .sh).
  • scripts/ — utilities (EPUB builder, link/mermaid/cross-ref validators). Not the product.
  • 02-memory/*.md — CLAUDE.md templates users copy into their own projects. Don't confuse with this file.
  • openspec/ — spec-driven change proposals.

Hard rules

  • YOU MUST NOT commit or push without explicit user request.
  • YOU MUST NOT add Co-Authored-By: Claude to any commit message.
  • Always activate .venv before running Python scripts (check venv/, .venv/, env/).
  • Internal links use relative paths (e.g. 01-slash-commands/README.md); anchors use #heading-name.
  • Code fences must declare a language (bash, python, json, …) — the cross-reference check fails otherwise.
  • External URLs must be reachable and stable. No ephemeral links.
  • Mermaid diagrams must parse (validated pre-commit, and only when mmdc is installed — the check skips with a warning otherwise). A broken EPUB build is usually invalid Mermaid or a missing/failing mmdc.
  • Commit format: type(scope): subject where scope matches the module folder (e.g. feat(slash-commands):, docs(memory):, fix(README):).
  • Do not reorganize the 01-10- numbering. The order is the curriculum.

Read the full file on GitHub · 63 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 · 63 lines · 883 tokens per session scan A 035a4879fe9b

Subscribe to this mod's changes

claude-howto CLAUDE.md is an instructions file published in the GitHub repository luongnv89/claude-howto (41,418 stars, last pushed 3d ago), licensed MIT. It adds 883 tokens to every session, about $0.0044 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 2026-08-30.

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