Teaching the AI Your Standards

Cursor Rules are persistent instructions that tell the AI how to behave. They're the difference between generic AI output and code that matches your team's exact conventions — because LLMs don't retain memory between completions, rules provide that persistent context. There are four kinds:

MDC File Structure

---
description: Enforce TypeScript best practices for components
globs: src/components/**
alwaysApply: false
---
# Component Standards
- Use functional components exclusively
- Prefer named exports over default exports
- Always define a Props interface
- Reference the canonical example: @src/components/Button.tsx

The Four Application Types

• Always Apply: alwaysApply: true — loaded into every agent interaction
• Apply Intelligently: the agent fetches the rule based on its description when relevant
• Apply to Specific Files: auto-attached when the file being edited matches globs
• Apply Manually: only when you @-mention the rule by name

Best Practices (from the official docs)

• Keep rules under 500 lines — split large rules into composable files
• Reference files with @filename instead of pasting code into the rule
• Don't copy entire style guides in — link the canonical examples
• Generate rules fast: type /create-rule in the agent input