Karpathy’s CLAUDE.md guide shot to the top of GitHub trends with more than 220,000 stars. It’s just 65 lines long, yet it pushed AI coding accuracy from 65% to 94%. Most developers haven’t even skimmed it, so here’s what you need. The file lays out four simple rules. First: think before you code. Spell out your assumptions, ask questions if something’s unclear and never guess. Second: simplicity first. Write only the minimal code needed. Skip abstractions nobody asked for. Third: surgical changes. Don’t touch unrelated code. Every modified line must tie back to the request. Fourth: goal‐oriented execution. Turn vague instructions into clear, testable success criteria before writing a single line. That’s it—65 lines, four rules, and a jump to 94% precision. Bookmark it now.