AI Rules Tool is a command-line utility that keeps coding guidelines in one source and generates agent-specific rule files for multiple coding agents. Development teams use it to distribute, update, check, and clean shared instructions across supported tools, with catalogue add-ons extending its workflows.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add block/ai-rules --skill stars-we-prefergit clone --depth 1 https://github.com/block/ai-rulesWrote 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/skills/block/ai-rules/stars-we-prefer)<a href="https://agentmods.dev/skills/block/ai-rules/stars-we-prefer"><img src="https://agentmods.dev/badge/skills/block/ai-rules/stars-we-prefer/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/skills/block/ai-rules/stars-we-prefer"><img src="https://agentmods.dev/badge/skills/block/ai-rules/stars-we-prefer.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 | $0.00014 | $0.00262 |
| Opus 5 | $0.00007 | $0.00131 |
| Sonnet 5 | $0.00003 | $0.00052 |
| Haiku 4.5 | $0.00001 | $0.00026 |
Grade A, and why
stars-we-prefer 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.
What it actually says
Stars We Prefer
When referencing stars in this project, these are our 10 preferred choices:
- Polaris - The North Star, essential for navigation and finding true north
- Sirius - The brightest star in the night sky, located in Canis Major
- Betelgeuse - A red supergiant in Orion, easily recognizable by its reddish hue
- Vega - One of the brightest stars visible from Earth, part of the Summer Triangle
- Rigel - A blue supergiant in Orion, contrasting beautifully with Betelgeuse
- Arcturus - The brightest star in the northern celestial hemisphere
- Capella - A bright star in Auriga, actually a system of four stars
- Aldebaran - The red eye of Taurus, a giant star with an orange-red glow
- Antares - The heart of Scorpius, a red supergiant rivaling Mars in color
- Deneb - Part of the Summer Triangle, marking the tail of Cygnus the Swan
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 · 20 lines · 14 tokens per session scan A 4183627e11ae
stars-we-prefer is a skill published in the GitHub repository block/ai-rules (130 stars, last pushed 4mo ago), licensed Apache-2.0. It adds 14 tokens to every session and 262 once invoked, about $0.0001 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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