rulens: Instructions file for Claude Code

CLAUDE.md

rulens CLAUDE.md is an instructions file for Claude Code from MH4GF/rulens. It costs 1,564 tokens per session, scanned A, original, MIT.

Project instructions for Rulens, a command-line tool that documents linting rules from tools such as Biome and ESLint.

In plain words
What is it for?
Use them when modifying lint-rule extraction, Markdown generation, builds, formatting, or the project’s requirements and task list.
Why use it?
They point developers to the required documentation and project commands, reducing inconsistent changes to the tool and its records.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md; names the TodoWrite tool; mentions Claude Code.

This is MH4GF/rulens's own configuration. It tells Claude Code how to work on rulens 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 rulens configures →

Reuse

Borrowing it

Nothing to install: this file belongs to MH4GF/rulens. 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/MH4GF/rulens/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/MH4GF/rulens

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.

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README.md
[![agentmods](https://agentmods.dev/badge/instructions/mh4gf/rulens/claude-md.svg)](https://agentmods.dev/instructions/mh4gf/rulens/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/mh4gf/rulens/claude-md"><img src="https://agentmods.dev/badge/instructions/mh4gf/rulens/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,564 This file is loaded in full into every session.
When invoked 1,564 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 $0.01564 $0.01564
Opus 5 $0.00782 $0.00782
Sonnet 5 $0.00313 $0.00313
Haiku 4.5 $0.00156 $0.00156

Measured 8d ago against content hash 9155597b8185, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

rulens 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 8d 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 · 122 lines

How it starts

The opening of the file, as written. The whole thing — 122 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

Rulens is a CLI tool for extracting, documenting, and formatting linting rules from various linting tools (currently supporting Biome and ESLint). It generates comprehensive Markdown documentation to help developers understand and follow the project's coding standards.

Documentation

IMPORTANT: Always read all documentation in the docs/ directory at the start of each session. This includes:

  • docs/lint-rules.md - Explains linting rules and coding standards
  • docs/requirements.md - Project requirements and technical specifications
  • docs/todos.md - Task tracking for project implementation (CRITICAL to understand and update)
  • Any additional files in the docs/ directory

Pay special attention to docs/todos.md as it provides a clear roadmap of implemented features and pending tasks. Always update this file when implementing new features to reflect progress accurately.

Commands

  • Build: pnpm build - Build the project using tsup
  • Dev: pnpm dev - Watch mode for development
  • Format: pnpm fmt - Run all formatters (syncpack, biome)
  • Lint: pnpm lint - Run all linters (biome, tsc, syncpack) - Run after making changes
  • Test: pnpm test - Run all tests
  • Single test: pnpm test path/to/test.ts - Run specific test
  • Test with watch: pnpm test:watch - Run tests in watch mode
  • Coverage: pnpm test:coverage - Run tests with coverage report
  • Changeset: pnpm changeset - Create a new changeset (always write in English)

Workflow Commands: Always run pnpm lint and pnpm test after implementing new features to verify your changes.

Coding Guidelines

  • IMPORTANT: Always follow @docs/lint-rules.md as coding guideline
  • File Structure: Place tests alongside implementation files (e.g., foo.ts, foo.test.ts)
  • Type Safety: Avoid eslint-disable directives and type assertions (as keyword), use valibot for runtime type validation
  • External Data: Handle all external data (JSON, API responses) as untrusted and validate with valibot
  • Logging: Use the Logger class instead of console.log/error for consistent logging
  • Comments: Follow these guidelines for code comments:
    • Use JSDoc style comments for functions, classes, and interfaces
    • Write comments that explain "why" not "what" the code is doing
    • Avoid redundant comments that merely restate the code
    • Don't use comments for code organization or section markers; structure your code instead
    • Document non-obvious behavior, complex algorithms, or business rules
    • Keep comments up-to-date with code changes
    • Use English for all comments

Read the full file on GitHub · 122 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. 8d ago First seen · 122 lines · 1,564 tokens per session scan A 9155597b8185

Subscribe to this mod's changes

rulens CLAUDE.md is an instructions file published in the GitHub repository MH4GF/rulens (11 stars, last pushed 1y ago), licensed MIT. It adds 1,564 tokens to every session, about $0.0078 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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