Write rules once so Claude remembers your voice

Stop re-explaining yourself. Put your rules in one place the AI reads every time.

If you've ever typed "shorter, less formal, no exclamation marks" for the tenth time, you're doing the AI's memory work for it. Write your rules down once, in a place it reads at the start of every conversation.

Where the rules go

In Claude, the simplest home is a Project: create one for your business and paste your rules into its instructions. Everything you ask inside that project follows them. If you work in Claude Code, the same rules go in a file called CLAUDE.md.

What to write

Start with five sections, a few lines each:

1. Who I am and what I sell. One paragraph. Your offer, your prices, who your customers are.
2. How I write. Greeting, sign-off, maximum length, words you never use. Paste two real emails you wrote and liked.
3. What you may never do. Send email, promise discounts, invent features, give legal advice. Hard limits go in capitals.
4. How I want answers. "Lead with the answer. No preamble. Bullet points only when there are more than three items."
5. Facts to check against. Where your price list, terms and help docs live, so it checks rather than guesses.

Make rules specific

"Be concise" means nothing. "Three short paragraphs, no paragraph longer than three sentences" is a rule the AI can follow and you can check. Every time you correct it, ask whether the correction should become a rule. If you'd say it again, write it down.

Keep it short

A rules file that grows to ten pages gets followed less, not more. Once a month, delete rules that no longer matter and merge ones that say the same thing. Aim for something you could read in two minutes.

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