CLAUDE.md File: What It Is, Where It Goes, 3 Templates

A CLAUDE.md file is a plain-text Markdown file that Claude Code reads at the start of every session, so you can write down your rules, context and preferences once instead of repeating them in every conversation. Put it in a project's main folder for that project's rules, or in ~/.claude/CLAUDE.md for rules that apply to everything you do. Claude treats it as guidance rather than hard settings, so short, specific instructions work best.

Markdown is simply text with a few symbols for structure: # starts a heading and - starts a bullet. You don't need anything else to write a good CLAUDE.md.

How CLAUDE.md works

Every Claude Code session starts with a fresh memory. Two things carry knowledge from one session to the next: CLAUDE.md files that you write, and auto memory notes that Claude writes for itself.

Both are context, not enforced settings: Claude reads them and tries to follow them, as Anthropic's memory docs explain. To block something no matter what, use a permission rule instead, covered further down.

Where CLAUDE.md files go

~ means your home folder (%USERPROFILE% on Windows), and ./ means the main folder of your project.

Claude Code loads the CLAUDE.md in the folder you start it in and in every folder above it, and the files add up rather than replace each other. A CLAUDE.md inside a subfolder loads only once Claude starts working with files in that subfolder.

Because the most specific file is read last, a project rule sits closest to the work. Still, avoid contradicting your personal file, because when two rules conflict Claude may follow either one.

How to create one

1. Open your project folder in Claude Code. In the terminal, move into the folder and run claude; in the desktop app, use the Code tab and Select folder.
2. Run /init. Claude looks through the folder and writes a starter CLAUDE.md. If one already exists, it suggests improvements instead of overwriting it.
3. Or let Claude interview you. For a folder with little in it yet, the prompt below gets better results than /init.
4. Edit it. /memory lists your CLAUDE.md files and opens one in your editor, or you can simply say "add this rule to CLAUDE.md".
5. Reload it. The file is read at session start, so run /clear or start a new session after editing; Anthropic's prompt caching page explains why mid-session edits wait.
6. Check that it loaded. Run /context and look for the file under Memory files.

I want a CLAUDE.md for this folder. Ask me up to 8 questions, one at a time, about my business, who the work is for, my tone of voice, the rules I always want followed and what "done" means for me. Then write a CLAUDE.md under 60 lines with clear headings, and show it to me before you save it.

What to put in it, and what to leave out

Treat CLAUDE.md as the place for things you would otherwise re-explain. A good trigger for a new line is Claude making the same mistake twice, or you typing the same correction you typed last week.

If your rules already live in another file, pull it in with an @ import such as @brand/voice.md instead of copying it. Imported files also load at startup, so imports keep things organized but don't make the file any lighter.

Three copy-ready templates

Replace everything in square brackets, delete what doesn't apply, and keep the result short. Each one is a starting point to trim after a week of real use.

Template 1: business owner

Save this as ~/.claude/CLAUDE.md to apply it everywhere, or as CLAUDE.md in the folder you use for admin work.

# About me and my business
- I run [BUSINESS NAME], a [TYPE OF BUSINESS] in [CITY OR MARKET].
- Customers are [WHO THEY ARE]. Main products or services: [LIST].
- I'm not a developer. Explain anything technical in one plain sentence.

# How to work with me
- Ask me questions before starting anything that takes more than a few steps.
- Show me a short plan before changing more than 3 files.
- Reply in [LANGUAGE], in short paragraphs, without jargon.

# Rules that always apply
- Never send emails, messages or payments. Prepare drafts for me to send.
- Never delete files. Move anything you want removed into a folder called _trash.
- Never invent numbers, prices or facts. If something is missing, ask me.
- Currency is [CURRENCY]. Dates are written [DATE FORMAT].

# Files and folders
- Incoming documents are in /inbox. Finished work goes in /output.
- Name files like YYYY-MM-DD_topic.

# When you finish a task
- List what you changed, what you couldn't do and anything you were unsure about.

# Compact instructions
When compacting, keep the list of files changed and any open questions.

The last section uses a feature from Anthropic's docs: a "Compact instructions" heading tells Claude what to keep when it summarizes a long conversation.

Template 2: marketer

Save this as CLAUDE.md in your marketing folder. For full marketing workflows that use it, see Claude Code for marketers.

# Brand
- Brand: [BRAND NAME]. We sell [OFFER] to [AUDIENCE].
- Voice: [THREE ADJECTIVES]. We sound like [EXAMPLE], never like [ANTI-EXAMPLE].
- Words we never use: [LIST].
- Spelling: [US OR UK] English.

# Facts and claims
- Use only the facts in /brand/facts.md and in the files I give you.
- Every statistic needs a source link. If you can't find one, leave the number out.
- Don't name competitors unless I ask.

# Channels and formats
- LinkedIn: under [NUMBER] words, one idea per post.
- Email: subject line under [NUMBER] characters, one call to action.
- Instagram captions: the hook goes in the first line, under [NUMBER] words in total.

# Files
- Briefs are in /briefs. Drafts go in /drafts, one file per piece, named channel_topic_date.

# Before you say you're done
- Check every claim against the source files and list anything unsupported.

Template 3: website project

Save this as CLAUDE.md in the main folder of the site. The guide to building a website with AI walks through a full project that pairs well with it.

# Project
- Website for [BUSINESS NAME]: [WHAT THE SITE IS FOR].
- The one action we want from visitors: [FOR EXAMPLE, BOOK A CALL].
- Built with [STACK, FOR EXAMPLE PLAIN HTML AND CSS]. Hosted on [HOST].

# Commands
- Preview locally: [COMMAND]
- Check before publishing: [COMMAND]

# Design rules
- Colors: [HEX CODES]. Fonts: [FONTS]. Keep plenty of white space.
- Mobile first: check every change at phone width before saying it's done.
- Every image needs alt text. Buttons say what happens next ("Book a call", not "Submit").

# Content rules
- Use only the copy in /content and facts I confirm. No invented reviews, numbers or logos.
- Every page needs its own title and meta description.

# Don't
- Don't add new libraries, plugins or services without asking me.
- Don't change domain, DNS or hosting settings.

# Done means
- The check command passes, the page works at phone width, and you list what you changed.

When CLAUDE.md isn't enough

The guide to creating a Claude skill shows how to turn a procedure into a skill. For deny rules, Anthropic's permissions guide has the syntax, and our Claude Code cheat sheet includes a starter settings file.

Keeping CLAUDE.md lean also saves usage, because it loads into every session. The guide to Claude Code usage limits explains how much the size of your context matters.

When Claude ignores your CLAUDE.md

• It never loaded. Run /context and check for it under Memory files; if it's missing, it is in the wrong folder.
• You edited it mid-session. Run /clear or start a new session so the new version loads.
• It is too long or too vague. Cut anything Claude already does on its own, and rewrite fuzzy rules as checkable ones.
• Two rules conflict. Look across your personal file, the project file and any subfolder files, and delete one of them.
• It needs to be a hard rule. Move it into a permission rule or a hook.

What to do next

Open your most-used project folder, run /init or the interview prompt, and keep the result under 60 lines for the first week. Every time you correct Claude, ask whether that correction belongs in the file, and remove anything Claude already does on its own. The beginner tutorial shows CLAUDE.md working inside a real project, and the Claude Code course has a lesson dedicated to the CLAUDE.md file, followed by skills and MCP.