react-expert
An agent skill by Jeffallan, from Jeffallan/claude-skills. Tags: javascript, performance, react, state-management, web.
What it does
Use when building React 18+ applications in .jsx or .tsx files, Next.js App Router projects, or create-react-app setups. Creates components, implements custom hooks, debugs rendering issues, migrates class components to functional, and implements state management. Invoke for Server Components, Suspense boundaries, useActionState forms, performance optimization, or React 19 features.
Install
With the skills CLI, which installs into Claude Code, Codex, Cursor and other agents:
npx skills add Jeffallan/claude-skills --skill react-expertOr copy the skill folder into Claude Code's skills directory by hand (~/.claude/skills for every project, or .claude/skills inside one):
git clone --depth 1 https://github.com/Jeffallan/claude-skills
cp -r claude-skills/skills/react-expert ~/.claude/skills/react-expertSafety box score
Grade A, minimal risk: 7 of 100 risk points, rated 2026-10-19. The grade rates what the skill and its scripts can reach on the machine of whoever installs it, across eight categories from shell execution to secrets access. How the score works.
This skill is a React implementation guide that mainly edits project source and test files, with no bundled scripts or installers. The main risks are local command execution during validation and broad code changes inside the working tree; it does not appear to reach outside the project or touch secrets or privileges.
| Category | Level | Why |
|---|---|---|
| Code & shell execution | 1 (low) | The workflow explicitly tells the agent to run local commands like `tsc --noEmit` and tests, so it can execute shell commands on the user's machine, but only in the repo context. |
| Network access | 0 (none) | There are no shipped scripts that download data or send it to remote hosts; the `fetch(...)` snippets are examples of app code, not runtime behavior of the skill itself. |
| Filesystem reach | 1 (low) | The skill is for implementing and migrating React code, so it will create and edit `.jsx`/`.tsx` and test files in the working tree, but it does not mention paths outside the project. |
| Secrets & credentials | 0 (none) | Nothing in the files asks for tokens, passwords, `.env` contents, keychains, or browser sessions. |
| Privilege & persistence | 0 (none) | There is no `sudo`, global install, service registration, shell startup editing, or other privilege-changing step in the shipped files. |
| Instruction hijack surface | 0 (none) | I did not find prompt-injection content such as instructions to ignore policies, hide actions, or follow remote instructions. |
| Irreversible actions | 0 (none) | The skill does not push, deploy, publish, pay, book, or delete anything; its purpose is local code implementation. |
| Transparency | 0 (none) | All shipped files are readable markdown and code examples; there are no binaries, minified blobs, or decoded-at-runtime payloads. |
Before installing
- Read `SKILL.md` and confirm you are comfortable with it running `tsc --noEmit` and tests locally.
- Use a disposable branch or scratch repo first, since the skill is meant to edit project files in place.
- Verify there are no hidden scripts or binaries beyond the markdown files shown here.
Rated 2026-10-19 by an automated review of 8 files from the skill's repository.
Source
- Repository
- Jeffallan/claude-skills (all skills from this repository)
- Path
- skills/react-expert/SKILL.md
- Branch
- main
- Updated
- 2026-09-19
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