If you set up your .cursorrules file weeks ago and Cursor still feels like it hasn't changed — this is for you.
Most developers write cursor rules once, check the box, and move on. Then they wonder why Cursor keeps suggesting the wrong patterns, ignoring their preferred stack, or generating code they immediately rewrite.
The rules aren't broken. They're being ignored. Here's why.
1. Your rules are too vague to act on
Compare these two rules:
Bad: "Write clean code"
Better: "Prefer early returns over nested conditionals. Functions should do one thing. Max 40 lines per function."
Cursor is a language model. It responds to specific, unambiguous instructions — not abstract goals. Vague rules get averaged into the model's general behavior and disappear.
Fix: Rewrite every rule as a constraint with a measurable outcome.
2. You're fighting the model's defaults
Some things are deeply embedded in the model's training. Telling it "never use console.log" might work 80% of the time — but under pressure (complex debugging, long context), it reverts.
The rules that stick are the ones that redirect behavior, not fight it head-on.
Bad rule: "Never use any" (TypeScript)
Better: "When you would use any, use unknown instead and add a type guard. If you truly cannot avoid it, add an inline comment explaining why."
The second version gives the model an acceptable path forward.
3. Your rules file is too long
There's a practical context limit. A .cursorrules file with 200 lines competes with your actual code for attention in context.
Fix: Keep your rules file under 80 lines. Prioritize rules that address recurring mistakes — not aspirational guidelines.
4. The rules don't reflect your actual project
A generic .cursorrules template you found online will underperform a project-specific one you wrote yourself. The model can't know your business domain, your team's conventions, or which libraries you've banned unless you tell it.
Fix: After every session where you corrected the model, ask: "Could a rule have prevented this?" If yes, add it.
5. You set them up but never iterated
Cursor Rules are not a config file. They're a living document. Your project evolves. Rules that made sense in week 1 may be wrong in week 8.
The pattern that works:
- Something breaks → add a rule
- AI suggests wrong pattern → add a rule
- You find yourself repeating context → add a rule
If you want a head start with production-tested rules — the Cursor Rules Pack v2 includes 35+ rules covering dependency discipline, error handling, TypeScript strictness, commit hygiene, and more.
The goal isn't a perfect .cursorrules file. It's a file that gets slightly less wrong every week.
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