Claude Code

The 20 KB File That Stops Claude Doing Four Dumb Things

The 20 KB file that stops Claude doing the four things that waste your time

3min read
3prompts to copy
15sections

What It Is

One file, no code

The repo is multica-ai/andrej-karpathy-skills. It is 199,884 stars, 20,560 forks, and 20 KB total, because the entire repository is a single CLAUDE.md file with no code in it at all.

It is a list of behaviours you are telling Claude NOT to do, derived from Andrej Karpathy observations on where LLMs go wrong when they write code. Most people try to make AI better by adding instructions. This works by subtracting.

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