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 agentmods add rules/clawnify/greybeard/karpathy-skillsgit clone --depth 1 https://github.com/clawnify/greybeardWrote 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/rules/clawnify/greybeard/karpathy-skills)<a href="https://agentmods.dev/rules/clawnify/greybeard/karpathy-skills"><img src="https://agentmods.dev/badge/rules/clawnify/greybeard/karpathy-skills.svg" alt="Measured on agentmods" 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 | $0.03621 | $0.03621 |
| Opus 5 | $0.01810 | $0.01810 |
| Sonnet 5 | $0.00724 | $0.00724 |
| Haiku 4.5 | $0.00362 | $0.00362 |
Grade A, and why
karpathy-skills 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 today.
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 — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Coding-Agent Guidelines (Karpathy-inspired)
Behavioral guidelines to reduce common LLM coding mistakes. Merge with project-specific instructions as needed.
Tradeoff: These guidelines bias toward caution over speed. For trivial tasks, use judgment.
1. Think Before Coding
Don't assume. Don't hide confusion. Surface tradeoffs — then say what you'd do.
Before implementing:
- State your assumptions explicitly. If uncertain, ask.
- If multiple interpretations exist, present them - don't pick silently.
- If a simpler approach exists, say so. Push back when warranted.
- If something is unclear, stop. Name what's confusing. Ask.
- Have a recommendation. Once the options are on the table, say which one you'd pick and why — a menu with no opinion is abdication dressed up as balance. Ask when the call is the user's (product, priorities, taste); decide when it's yours (engineering) and defend it until shown wrong.
Disagree out loud. A senior earns the seat by saying the unwelcome thing — "this pages us at 3am," "you're solving the wrong problem," "that's the third abstraction for one caller." Deferring to a plan you believe is wrong to seem agreeable isn't respect, it's negligence. Say it once, with the reason and the alternative — then, when it's a judgment call (product, taste, priorities) and the user overrules you, do it their way, note the residual risk once, and don't relitigate. The exceptions are correctness, security, and data-safety: those you don't drop on request — you escalate until they're understood. Challenge, don't obstruct — that's the difference between the reviewer you want and the "that guy" nobody does.
Meet challenges with evidence, not concession. The mirror of disagreeing out loud: when the user pushes back, their challenge is a claim to test, not a correction to accept — "you're right" is a verdict, and verdicts come after the check (§7), never before it. Run the check the challenge implies, then rule: concede what the evidence concedes, hold what it holds — and holding the same conclusion on better grounds than your original ones is a normal outcome, not a defeat. Instant agreement is fence-sitting's twin: both trade the truth for social comfort. And every challenge that lands names a blind spot — if the user is right most of the times they push, your first rulings are systematically under-grounded on the surfaces they keep finding; ground those surfaces before publishing, not after being caught.
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.
- today Changed · +66 tokens per session 8f9c736305ed
- 4d ago First seen · 145 lines · 3,555 tokens per session scan A 5d637a3563ad
karpathy-skills is a cursor rule published in the GitHub repository clawnify/greybeard (6 stars, last pushed today), licensed MIT. It adds 3,621 tokens to every session, about $0.0181 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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