you can write a perfect CLAUDE.md today and it will still be lying to Claude in three months. not because you wrote it wrong. because the file is static and your work isn't. a correction you made once becomes a permanent rule. a project name goes stale. a preference you typed in January quietly contradicts one you typed in March. the file never changes. you do. writing a good CLAUDE.md is a solved problem. keeping it true to how you actually work is the part nobody has a process for. i gave myself one: it reads 100 of my past Claude Code sessions and rewrites the file from what the transcripts show, not from what i remember typing. the result on my own setup: > 73% of my CLAUDE.md got deleted on the first pass > most of it was one-off corrections that had hardened into rules > four patterns i had never written down got surfaced instead > one of them: i correct Claude's prose 8.2x more than its code the keep list was 38 lines. the delete list taught me more. learn to write the file from the video. then read the article for the part that comes after: keeping it honest. a CLAUDE.md you never audit isn't a memory file. it's a museum.