react

react is a cursor rule for Cursor from toptalentcoder/Cursor-AwesomeRules. It costs 454 tokens per session, scanned A, a copy of react, CC0-1.0.

A set of React guidelines, where React is a JavaScript library for building user interfaces from reusable components. It covers components, hooks, state and rendering performance.

In plain words
What is it for?
Use it when creating or reviewing React components, custom hooks, shared state, lists, lazy-loaded content and TypeScript props.
Why use it?
It helps keep interfaces divided into focused pieces and avoids common problems such as incorrect hook usage, unnecessary updates and overly complicated state.

Cursor rule for Cursor

Written for Cursor: a Cursor rule (.mdc).

Good fit Use it when creating or reviewing React components, custom hooks, shared state, lists, lazy-loaded content and TypeScript props.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/toptalentcoder/cursor-awesomerules/react
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo
git clone --depth 1 https://github.com/toptalentcoder/Cursor-AwesomeRules

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for react

README.md
[![agentmods](https://agentmods.dev/badge/rules/toptalentcoder/cursor-awesomerules/react/github.svg)](https://agentmods.dev/rules/toptalentcoder/cursor-awesomerules/react)
Your own site
<a href="https://agentmods.dev/rules/toptalentcoder/cursor-awesomerules/react"><img src="https://agentmods.dev/badge/rules/toptalentcoder/cursor-awesomerules/react/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for react

Your own site · 80×15
<a href="https://agentmods.dev/rules/toptalentcoder/cursor-awesomerules/react"><img src="https://agentmods.dev/badge/rules/toptalentcoder/cursor-awesomerules/react.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 454 This file is loaded in full into every session.
When invoked 454 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 97% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00454 $0.00454
Opus 5.5 $0.00182 $0.00182
Sonnet 5.5 $0.00091 $0.00091
Haiku 4.5 $0.00045 $0.00045

Measured 1mo ago against content hash 5b799b05bcf2, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

react scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

97% identical to react — 7 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

rules-new/react.mdc · 78 lines

What it actually says

React Best Practices

Component Structure

  • Use functional components over class components
  • Keep components small and focused
  • Extract reusable logic into custom hooks
  • Use composition over inheritance
  • Implement proper prop types with TypeScript
  • Split large components into smaller, focused ones

Hooks

  • Follow the Rules of Hooks
  • Use custom hooks for reusable logic
  • Keep hooks focused and simple
  • Use appropriate dependency arrays in useEffect
  • Implement cleanup in useEffect when needed
  • Avoid nested hooks

State Management

  • Use useState for local component state
  • Implement useReducer for complex state logic
  • Use Context API for shared state
  • Keep state as close to where it's used as possible
  • Avoid prop drilling through proper state management
  • Use state management libraries only when necessary

Performance

  • Implement proper memoization (useMemo, useCallback)
  • Use React.memo for expensive components
  • Avoid unnecessary re-renders
  • Implement proper lazy loading
  • Use proper key props in lists
  • Profile and optimize render performance

Forms

  • Use controlled components for form inputs
  • Implement proper form validation
  • Handle form submission states properly
  • Show appropriate loading and error states
  • Use form libraries for complex forms
  • Implement proper accessibility for forms

Error Handling

  • Implement Error Boundaries
  • Handle async errors properly
  • Show user-friendly error messages
  • Implement proper fallback UI
  • Log errors appropriately
  • Handle edge cases gracefully

Testing

  • Write unit tests for components
  • Implement integration tests for complex flows
  • Use React Testing Library
  • Test user interactions
  • Test error scenarios
  • Implement proper mock data

Accessibility

  • Use semantic HTML elements
  • Implement proper ARIA attributes
  • Ensure keyboard navigation
  • Test with screen readers
  • Handle focus management
  • Provide proper alt text for images

Code Organization

  • Group related components together
  • Use proper file naming conventions
  • Implement proper directory structure
  • Keep styles close to components
  • Use proper imports/exports
  • Document complex component logic
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 78 lines · 454 tokens per session scan A 5b799b05bcf2

Subscribe to this mod's changes

react is a cursor rule published in the GitHub repository toptalentcoder/Cursor-AwesomeRules (6 stars, last pushed 1y ago), licensed CC0-1.0. It adds 454 tokens to every session, about $0.0018 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 97% identical to react, differing in 7 lines, and is treated as a copy.