Write your rules file

Claude Code automatically reads a file called CLAUDE.md when it starts in a folder. Everything you write there applies to every conversation. It is the most important file of your second brain: it turns a general assistant into a librarian who knows your rules.

What it contains

1. Who you are, in two or three sentences. Claude files better when it knows what matters to you.
2. The folders and what each one holds.
3. The format of a note: a header (title, type, theme, dates, sources), a summary, key points, links.
4. The themes: a closed list.
5. The three operations: add, ask, check (module 4).
6. What Claude never does: modify raw/, make things up.

The most important choice: a closed list of themes

Free tags drift: after a month you have client, clients, customer and work-client. A closed list of 5 to 8 themes, written in the rules file, forces each note into one clear place. Claude can then answer a question by opening only one theme, which is where the savings of module 5 come from.

5 to 8 themes. One theme per note. A new theme only when nothing fits.

Good themes are areas of your life, not keywords: client-work, employment-law, reading, health. If you hesitate between two themes for half your notes, merge them.

Fill in the template

Open CLAUDE.md in the kit and replace everything between square brackets. Do not touch the rest at first: it works as is. You will adjust it after a few weeks, when you see what Claude does wrong. A good rules file grows from real mistakes, not from rules imagined in advance.