# What is Rules?

Persistent instructions in `.cursor/rules` that shape how the AI behaves across the whole project. They encode your standards so you do not repeat them in every prompt.

## In real work

Add to Rules: always use Zod for API validation. Never use any instead of typed interfaces. Apply to all new files.

## Related terms

- [Agent](https://prompthausapp.com/learn/agent.md)
- [Tab](https://prompthausapp.com/learn/tab.md)
- [MCP](https://prompthausapp.com/learn/mcp.md)
- [Context](https://prompthausapp.com/learn/context.md)
- [Plan Mode](https://prompthausapp.com/learn/plan-mode.md)

## How is this different from Googling it?

Google gives a definition. Prompthaus pairs each term with how it shows up in standups, PRs, prompts, and design reviews—then quizzes you until the word sticks. One term a day on iPhone.

- Category: Using AI
- HTML: https://prompthausapp.com/learn/rules
- App Store: https://apps.apple.com/us/app/prompthaus-ai-vocabulary/id6776314407