Karpathy-inspired Claude Code guidelines

Install

/plugin marketplace add forrestchang/andrej-karpathy-skills
/plugin install andrej-karpathy-skills@karpathy-skills

This is third-party code. Review the repository files before installing.

What it does

A rules file based on Andrej Karpathy's observations about model weaknesses in coding. The first principle requires stating assumptions and asking when unclear. The second forbids abstractions and features beyond the request. The third limits edits to necessary lines, and the fourth turns tasks into verifiable success criteria.

Who it is for. Developers annoyed by bloated diffs and unrequested refactoring from their agent.

Example request

Add email validation to the signup form following karpathy-guidelines and leave other code alone

Limitations

These are instructions only, with no checks or hooks, so results depend on how well the model follows them. Install commands in the README point to the original forrestchang/andrej-karpathy-skills repo.

How to disable. Remove the andrej-karpathy-skills plugin or delete the section from the project's CLAUDE.md.

Security check

• Text instructions only

README in short

The README quotes Karpathy's post on LLM coding problems and offers four principles: think before coding, simplicity first, surgical changes, goal-driven execution. The rules install as a Claude Code plugin or get appended to a project CLAUDE.md. A Cursor rule is included. The author notes the rules favor caution over speed.

SKILL.md

---
name: karpathy-guidelines
description: Behavioral guidelines to reduce common LLM coding mistakes. Use when writing, reviewing, or refactoring code to avoid overcomplication, make surgical changes, surface assumptions, and define verifiable success criteria.
license: MIT
---

# Karpathy Guidelines

Behavioral guidelines to reduce common LLM coding mistakes, derived from [Andrej Karpathy's observations](https://x.com/karpathy/status/2015883857489522876) on LLM coding pitfalls.

**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.**

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.

## 2. Simplicity First

**Minimum code that solves the problem. Nothing speculative.**

- No features beyond what was asked.
- No abstractions for single-use code.
- No "flexibility" or "configurability" that wasn't requested.
- No error handling for impossible scenarios.
- If you write 200 lines and it could be 50, rewrite it.

Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.

## 3. Surgical Changes

**Touch only what you must. Clean up only your own mess.**

When editing existing code:
- Don't "improve" adjacent code, comments, or formatting.
- Don't refactor things that aren't broken.
- Match existing style, even if you'd do it differently.
- If you notice unrelated dead code, mention it - don't delete it.

When your changes create orphans:
- Remove imports/variables/functions that YOUR changes made unused.
- Don't remove pre-existing dead code unless asked.

The test: Every changed line should trace directly to the user's request.

## 4. Goal-Driven Execution

**Define success criteria. Loop until verified.**

Transform tasks into verifiable goals:
- "Add validation" → "Write tests for invalid inputs, then make them pass"
- "Fix the bug" → "Write a test that reproduces it, then make it pass"
- "Refactor X" → "Ensure tests pass before and after"

For multi-step tasks, state a brief plan:

Related