Borrowing it
Nothing to install: this file belongs to mycelium-hq/ai-brain-starter. 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/mycelium-hq/ai-brain-starter/main/CLAUDE.mdgit clone --depth 1 https://github.com/mycelium-hq/ai-brain-starterWrote 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/mycelium-hq/ai-brain-starter/claude-md)<a href="https://agentmods.dev/instructions/mycelium-hq/ai-brain-starter/claude-md"><img src="https://agentmods.dev/badge/instructions/mycelium-hq/ai-brain-starter/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/mycelium-hq/ai-brain-starter/claude-md"><img src="https://agentmods.dev/badge/instructions/mycelium-hq/ai-brain-starter/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 | $0.01723 | $0.01723 |
| Opus 5 | $0.00861 | $0.00861 |
| Sonnet 5 | $0.00345 | $0.00345 |
| Haiku 4.5 | $0.00172 | $0.00172 |
Grade A, and why
ai-brain-starter 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 9d 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 — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.
ai-brain-starter — Claude Instructions
Public repo rules — NEVER HARDCODE PERSONAL CONTEXT
This is a public repo that strangers fork to build their own vaults. The whole point is that it must work for people who are NOT the maintainer and are NOT on the maintainer's team.
Before writing or editing ANY file in this repo, scan for and remove:
- Personal names (the maintainer, their co-founders, their team, their advisors, their family)
- Company names the maintainer is affiliated with
- Personal vault and folder paths — the maintainer's own vault name, their team-folder name, any emoji-prefixed folder specific to one person's structure. Every folder in a user's vault is named by that user at install time. Never hardcode one, not even as a fallback: read it from config, detect it structurally, or take it as an argument. A hardcoded folder name is dead code for everyone except the person who wrote it.
- Personal frameworks the maintainer invented (a bespoke rating scale, a private roster of named advisors)
- Specific cities, countries, or geographies that aren't universal
- Substack URLs and personal blog links other than what already exists in the README/SKILL.md welcome message
- Real meeting names, real decision content, real strategic context
- Anecdotes that name real people or real situations
When you need to illustrate a pattern with an example, invent a fictional one. Generic placeholders ("a Google Drive shared folder", "a team member", "a co-founder") are always preferred over real names. If a fictional example would be confusing without context, use a clearly-marked one (# Example only — replace with your own).
Existing files that pre-date this rule may have personal references (the README's Background section names the maintainer as legitimate authorship attribution; the LICENSE carries their copyright; the CHANGELOG narrates the actual history of the repo's development). Don't touch those — they're load-bearing context. The rule applies to new content you add.
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.
- 9d ago First seen · 84 lines · 1,723 tokens per session scan A 49089de7b3c3
ai-brain-starter CLAUDE.md is an instructions file published in the GitHub repository mycelium-hq/ai-brain-starter (36 stars, last pushed today), licensed MIT. It adds 1,723 tokens to every session, about $0.0086 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 2026-08-31.
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