atom: Instructions file for Claude Code

CLAUDE.md

atom CLAUDE.md is an instructions file for Claude Code from machbuilds/atom. It costs 97 tokens per session, scanned A, original, MIT.

A pointer file telling Claude and other AI tools to read the repository's AGENTS.md file for project instructions. It is duplicated under several common instruction-file names so different coding tools find the same guidance.

In plain words
What is it for?
Use it at the start of an AI-assisted coding session to locate and follow the project's main agent instructions.
Why use it?
It keeps one shared instruction source instead of repeating rules in multiple files that could become inconsistent.

Instructions file for Claude Code

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

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

Reuse

Borrowing it

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

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 atom CLAUDE.md

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/machbuilds/atom/claude-md"><img src="https://agentmods.dev/badge/instructions/machbuilds/atom/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 97 This file is loaded in full into every session.
When invoked 97 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 $0.00097 $0.00097
Opus 5.5 $0.00039 $0.00039
Sonnet 5.5 $0.00019 $0.00019
Haiku 4.5 $0.00010 $0.00010

Measured 1mo ago against content hash c92ddc1e3504, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

atom 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.

CLAUDE.md · 11 lines

What it actually says

CLAUDE.md → AGENTS.md

Project instructions live in AGENTS.md. Read that file.

This forwarder exists so Claude Code's default CLAUDE.md auto-load works without duplicating content. Same pattern for GEMINI.md, .cursorrules, and .github/copilot-instructions.md.

If you are an AI tool reading this file: open AGENTS.md in this repo and follow the instructions there.

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 First seen · 11 lines · 97 tokens per session scan A c92ddc1e3504

Subscribe to this mod's changes

atom CLAUDE.md is an instructions file published in the GitHub repository machbuilds/atom (2 stars, last pushed 4mo ago), licensed MIT. It adds 97 tokens to every session, about $0.0004 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 2026-08-31.

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