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Bruno Ashford @brunoashfordSubscribeModule 4 · Lesson 4.3 · 12 min
Rules, Red Lines and Quality Bars
Write the rules Claude must follow, the things it must never do, and the standard every output must meet.
Use ← → to move. The marker highlights text and the pencil draws on the slide; navigation locks while you annotate. Undo removes the last mark, Esc exits.
1Separate three kinds of rules
Red lines are things that must never happen (sending, deleting, promising). Standards are how things are always done (formats, naming, tone). Quality bars are what good looks like before you see it (checked numbers, sources, length). Write each group under its own heading in CLAUDE.md.
2Write red lines as short, absolute sentences
Use NEVER and ALWAYS sparingly and only where you mean it. One rule per line. Explain the reason in a few words, because Claude applies rules better when it understands why.
Add a section called Red lines to CLAUDE.md with these rules, one per line, each with a short reason: never send emails or messages, only draft them; never edit files in the originals folder; never quote a price that is not in our price list; never put client names in file names; never guess a number that is missing from the data.3Define your quality bars
Quality bars turn "make it good" into a checklist Claude runs before handing work to you. Keep them measurable: every number has a source, drafts are under a word limit, spelling is US or UK.
Add a section called Quality bar to CLAUDE.md. Before giving me any deliverable, check: every number cites its source file, the recommendation comes first, it follows our voice rules, it uses UK spelling, and anything uncertain is marked as an assumption.4Test the red lines on purpose
Ask Claude to do something that breaks a rule and watch it refuse or ask. If it does not, the rule is unclear, buried or contradicted somewhere else. Fix the wording, not the model.
Please email the updated price list to all our clients now.5Know when a rule needs a hard block
Claude treats CLAUDE.md as context, not enforced configuration. For anything where one mistake would be serious, such as deleting records or touching payment files, also block it with permissions or a hook so it cannot happen even by accident. Module 11 shows you how.
Your best employee is not the one who works fastest. It is the one who knows what never to do without being told. Never quote a price you have not approved. Never promise a delivery date. Never forward a client's file to another client. That judgment is what makes delegation safe.
In this lesson you give Claude that judgment in writing. You will also learn an important limit: CLAUDE.md is guidance Claude follows very reliably, but it is not a lock. For the things that must be impossible, not just unlikely, you need permission settings and hooks, which we cover properly in Module 11.
Key points
- Red lines, standards and quality bars are three different things.
- One rule per line, with a short reason.
- Test every red line by trying to break it.
- Contradictory rules get followed unpredictably.
- CLAUDE.md guides. Permissions and hooks enforce.
Avoid
- Writing everything in capitals so nothing stands out.
- Rules that contradict each other in different sections.
- Relying only on CLAUDE.md for actions that must be impossible.
- Never testing whether the rules actually work.
A family law practice wrote six red lines, including never stating a likely outcome of a case and never including a client's name in a document meant for another matter. They tested each one by asking Claude to break it. Five held first time. The sixth failed because an older section of the handbook said to "personalise every letter with the client's full details". Removing the contradiction fixed it. They then added a permission rule so the archive folder could not be edited at all.