react-patterns

A reference guide to React component design, hooks, state management, performance, and TypeScript practices.

In plain words
What is it for?
Use it when designing components, extracting custom hooks, selecting state-management tools, or reviewing React application structure.
Why use it?
It provides shared rules for organizing React code and choosing where state and logic should live.

Skill for Claude CodeCodex

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 skills/ivanshtokov/copilot-kit/react-patterns
Any agent
npx skills add ivanshtokov/copilot-kit --skill react-patterns
Clone the repo
git clone --depth 1 https://github.com/ivanshtokov/copilot-kit

Made for: Claude Code, Codex.

Per session 21 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 871 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00021 $0.00871
Opus 5 $0.00010 $0.00436
Sonnet 5 $0.00004 $0.00174
Haiku 4.5 $0.00002 $0.00087

Measured yesterday against content hash 4fee12806d5f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

react-patterns 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 yesterday.

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-patterns — 1 line 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.

.github/skills/react-patterns/SKILL.md · 198 lines

How it starts

The opening of the file, as written. The whole thing — 198 lines — stays where its author put it; the contents beside it link to each section on GitHub.

React Patterns

Principles for building production-ready React applications.


1. Component Design Principles

Component Types

Type Use State
Server Data fetching, static None
Client Interactivity useState, effects
Presentational UI display Props only
Container Logic/state Heavy state

Design Rules

  • One responsibility per component
  • Props down, events up
  • Composition over inheritance
  • Prefer small, focused components

2. Hook Patterns

When to Extract Hooks

Pattern Extract When
useLocalStorage Same storage logic needed
useDebounce Multiple debounced values
useFetch Repeated fetch patterns
useForm Complex form state

Hook Rules

  • Hooks at top level only
  • Same order every render
  • Custom hooks start with "use"
  • Clean up effects on unmount

3. State Management Selection

Complexity Solution
Simple useState, useReducer
Shared local Context
Server state React Query, SWR
Complex global Zustand, Redux Toolkit

State Placement

Scope Where
Single component useState
Parent-child Lift state up
Subtree Context
App-wide Global store

4. React 19 Patterns

New Hooks

Hook Purpose
useActionState Form submission state
useOptimistic Optimistic UI updates
use Read resources in render

Compiler Benefits

  • Automatic memoization
  • Less manual useMemo/useCallback
  • Focus on pure components

5. Composition Patterns

Compound Components

  • Parent provides context
  • Children consume context
  • Flexible slot-based composition
  • Example: Tabs, Accordion, Dropdown

Render Props vs Hooks

Use Case Prefer
Reusable logic Custom hook
Render flexibility Render props
Cross-cutting Higher-order component

Read the full file on GitHub · 198 lines

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. yesterday First seen · 198 lines · 21 tokens per session scan A 4fee12806d5f

Subscribe to this mod's changes

react-patterns is a skill published in the GitHub repository ivanshtokov/copilot-kit (2 stars, last pushed 7mo ago), licensed MIT. It adds 21 tokens to every session and 871 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 97% identical to react-patterns, differing in 1 line, and is treated as a copy.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens

babysit-pr

Babysit a GitHub pull request after creation by continuously polling review comments, CI checks/workflow runs, and mergeability state until the PR is merged/closed or user help is required. Diagnose failures, retry likely flaky failures up to 3 times, auto-fix/push branch-related issues when appropriate, and keep…

openai/codex · 114 tokens

imagegen

Generate or edit raster images when the task benefits from AI-created bitmap visuals such as photos, illustrations, textures, sprites, mockups, or transparent-background cutouts. Use when Codex should create a brand-new image, transform an existing image, or derive visual variants from references, and the output…

openai/codex · 113 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

next-cache-components-optimizer

Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…

vercel/next.js · 170 tokens