React useEffect best practices from official docs. Use when writing/reviewing useEffect, useState for derived values, data fetching, or state synchronization. Teaches when NOT to use Effect and better alternatives.
インストール方法を見るインストールする前に、エージェントに与えられる指示の中身を確認できます。
Effects are an escape hatch from React. They let you synchronize with external systems. If there is no external system involved, you shouldn't need an Effect.
| Situation | DON'T | DO |
|---|---|---|
| Derived state from props/state | useState + useEffect | Calculate during render |
| Expensive calculations | useEffect to cache | useMemo |
| Reset state on prop change | useEffect with setState | key prop |
| User event responses | useEffect watching state | Event handler directly |
| Notify parent of changes | useEffect calling onChange | Call in event handler |
| Fetch data | useEffect without cleanup | useEffect with cleanup OR framework |
useSyncExternalStore when possible)const fullName = firstName + ' ' + lastNameNeed to respond to something?
├── User interaction (click, submit, drag)?
│ └── Use EVENT HANDLER
├── Component appeared on screen?
│ └── Use EFFECT (external sync, analytics)
├── Props/state changed and need derived value?
│ └── CALCULATE DURING RENDER
│ └── Expensive? Use useMemo
└── Need to reset state when prop changes?
└── Use KEY PROP on component
まだレビューはありません。使ってみた感想をお寄せください。
概要と使いどころ
Refactor bloated AGENTS.md, CLAUDE.md, or similar agent instruction files to follow progressive disclosure principles. Splits monolithic files into organized, linked documentation.
日本語の概要は準備中です。原文の説明を表示しています。
Create API handoff documentation for frontend developers. Use when backend work is complete and needs to be documented for frontend integration, or user says 'create handoff', 'document API', 'frontend handoff', or 'API documentation'.
日本語の概要は準備中です。原文の説明を表示しています。
Generate architecture documentation using C4 model Mermaid diagrams. Use when asked to create architecture diagrams, document system architecture, visualize software structure, create C4 diagrams, or generate context/container/component/deployment diagrams. Triggers include "architecture diagram", "C4 diagram", "system context", "container diagram", "component diagram", "deployment diagram", "document architecture", "visualize architecture".
日本語の概要は準備中です。原文の説明を表示しています。
Use when the user asks to run Codex CLI (codex exec, codex resume) or references OpenAI Codex for code analysis, refactoring, or automated editing. Uses GPT-5.2 by default for state-of-the-art software engineering.
日本語の概要は準備中です。原文の説明を表示しています。
This skill should be used when creating a Claude Code slash command. Use when users ask to "create a command", "make a slash command", "add a command", or want to document a workflow as a reusable command. Essential for creating optimized, agent-executable slash commands with proper structure and best practices.
日本語の概要は準備中です。原文の説明を表示しています。
Create high-quality git commits: review/stage intended changes, split into logical commits, and write clear commit messages (including Conventional Commits). Use when the user asks to commit, craft a commit message, stage changes, or split work into multiple commits.
日本語の概要は準備中です。原文の説明を表示しています。