react

react is a cursor rule for Cursor from shumatsumonobu/awesome-ai-rules. It costs 0 tokens per session (277 once invoked), scanned A, original, MIT.

A set of React and Next.js rules for building web components, loading data, handling forms, and organizing routes.

In plain words
What is it for?
It guides server and client components, data fetching, form mutations, loading and error screens, conditional styling, and route organization.
Why use it?
It keeps browser-specific advice limited to the web interface and avoids applying React patterns to unrelated project code.

Cursor rule for Cursor

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.

agentmods
npx agentmods add rules/shumatsumonobu/awesome-ai-rules/react
Clone the repo
git clone --depth 1 https://github.com/shumatsumonobu/awesome-ai-rules

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/shumatsumonobu/awesome-ai-rules/react.svg)](https://agentmods.dev/rules/shumatsumonobu/awesome-ai-rules/react)
Your own site
<a href="https://agentmods.dev/rules/shumatsumonobu/awesome-ai-rules/react"><img src="https://agentmods.dev/badge/rules/shumatsumonobu/awesome-ai-rules/react.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 277 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.00000 $0.00277
Opus 5 $0.00000 $0.00138
Sonnet 5 $0.00000 $0.00055
Haiku 4.5 $0.00000 $0.00028

Measured 4d ago against content hash 1ba2640a7bc6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 4d 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.

examples/nextjs-app/cursor/.cursor/rules/react.mdc · 33 lines

What it actually says

React Rules (auto-attached to .tsx/.jsx in packages/web/)

These rules ONLY activate when you're editing React files in the web package. The AI won't see them when editing database code, config files, or anything outside packages/web/*.tsx.

This prevents React-specific advice from leaking into non-React code.

Components

  • Server Components by default. "use client" only at the smallest leaf that needs hooks/events/browser APIs.
  • Define props as type ButtonProps = { ... } in the same file.
  • Use cn() (clsx + tailwind-merge) for conditional Tailwind classes.
  • Use forwardRef for components wrapping native elements.

Data Flow

  • Fetch data in Server Components with async/await.
  • Use Server Actions for mutations. useActionState for form state, useOptimistic for instant feedback.
  • Never use useEffect for data fetching.

Routing

  • Use loading.tsx for streaming, error.tsx for error boundaries with retry.
  • Use route groups (groupName) for layout organization.
  • Route handlers (app/api/) are for webhooks only.
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. 4d ago First seen · 33 lines · 0 tokens per session scan A 1ba2640a7bc6

Subscribe to this mod's changes

react is a cursor rule published in the GitHub repository shumatsumonobu/awesome-ai-rules (1 stars, last pushed 1mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 277 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.