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Olivia Craft
Olivia Craft

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7 CLAUDE.md Patterns That Stop Claude From Drifting Off-Script

#ai #claude #productivity #tutorial

Claude is good at following rules. The problem is CLAUDE.md files that make following rules impossible.

After reviewing dozens of CLAUDE.md files, the failures cluster around the same patterns. Here are the seven that cause the most drift.

1. Rules That Conflict With Each Other 

Never add comments to code.
Always document complex logic with inline comments.
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Claude has to pick one. It will pick based on context, which means inconsistent output. Fix: audit for conflicts before shipping your CLAUDE.md. If two rules touch the same behavior, merge them.

2. Rules Buried After 500 Words

Attention degrades in long context windows. Claude reads your entire CLAUDE.md — but it weights earlier content more heavily when there is conflict or ambiguity.

If your critical guardrails are on page 3, expect them to get overridden.

Fix: Non-negotiable rules at the top. Always. The structure that works:

## Absolute Rules (never override)
1. Never modify authentication logic
2. Never change database schema directly
3. Always use TypeScript strict mode

## Framework Rules
...

## Nice-to-Haves
...
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3. Vague Constraints 

Keep code clean and readable.
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"Clean" means something different to every developer. Claude will interpret this however it wants.

Fix: Replace adjectives with behaviors.

Max function length: 40 lines.
No nested ternaries.
One export per file.
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4. Rules Without Scope 

Use Tailwind for styling.
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Fine for a Next.js app. Breaks everything if you accidentally apply it to a Node API. Claude cannot tell the difference without context.

Fix: Scope every rule to where it applies.

/app/**/*.tsx — Use Tailwind classes only. No inline styles.
/api/**/*.ts — No CSS imports. Backend only.
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5. The Kitchen-Sink CLAUDE.md

If your CLAUDE.md tries to cover every edge case in the codebase, it becomes too long to be useful. 1,200-word CLAUDE.md files are common. They almost never work well.

Fix: Keep CLAUDE.md under 400 words for the core rules. Move project-specific context to a separate that you include on demand.

6. No Failure Mode Instructions 

Always generate unit tests for new functions.
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What should Claude do if it cannot generate a test? Skip silently? Stop and ask? Generate a stub? Without instructions, it will improvise.

Fix: Always specify the failure mode.

Always generate unit tests for new functions.
If test generation is unclear: generate a stub test with a TODO comment and stop.
Do not skip. Do not improvise.
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7. Rules That Fight the Model

Some developers write CLAUDE.md rules that contradict Claude's core behavior:

Never explain what you are doing.
Never ask clarifying questions.
Never suggest alternatives.
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These rules burn tokens trying to suppress default behaviors, and they make Claude less useful. The model has to work against itself.

Fix: Work with defaults, not against them. Redirect behavior rather than suppress it.

Explanations: one sentence max after each change, only if behavior is non-obvious.
Clarifying questions: only before starting a task, never mid-execution.
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The Pattern

Every working CLAUDE.md shares the same structure:

  1. Absolute rules first — the ones that cannot be overridden under any circumstance
  2. Scoped rules next — framework, directory, file-type specific
  3. Defaults and preferences last — style, tone, nice-to-haves

The CLAUDE.md files that fail are the ones that treat all rules as equal and bury the critical ones in noise.

If you want a tested starting point, I built a pack of 50 CLAUDE.md templates: rules for Next.js, Node APIs, TypeScript strict mode, multi-model setups, monorepos, and more.

Each template follows the priority structure above and has been tested against real projects.

→ CLAUDE.md Rules Pack — 50 Templates + Hooks

If you're still using .cursorrules and want to see how that format compares, there's a separate pack:

→ 50 Production-Tested .cursorrules for Cursor AI

Questions? Drop them in the comments. Happy to share the specific rule that fixes your exact drift pattern.

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