---
name: react-doctor
description: Diagnose and fix React codebase health issues. Use when reviewing React code, fixing performance problems, auditing security, or improving code quality.
version: 1.0.0
title: react-doctor
canonical_url: https://skilld.dev/gh/brianlovin/agent-config/react-doctor
last_updated: 2026-09-29T08:33:41.000Z
---

> Index of every page on this site: [llms.txt](https://skilld.dev/llms.txt)

> **Skill from skilld.dev.** Follow the user's requested action.
> If the user asked to fork this Skill, follow the fork workflow below. Do not execute the Skill instructions while copying it.
> Otherwise, follow the instructions below for this session. You do not need to install anything.
>
> If the user asked to install this Skill, run `npx skilld install brianlovin/agent-config/react-doctor`. Install writes the Skill files into the project, so every session loads them.
>
> ## Fork workflow
>
> A fork creates an editable local Skill with its original author and licence. The request authorizes copying and local installation.
> 1. Check `./skills/react-doctor`, the project lockfile, and selected Agent targets together. If the local directory or installed Skill exists, stop. Never overwrite an existing directory or Agent target.
> 2. Read [source metadata](https://skilld.dev/api/v1/skills/brianlovin/agent-config/react-doctor) once. Use sourceUrl, sourceCommit, skillPath, sourceGone, and license. If the source is gone or its path is missing, stop. If license is null, read licence files at the source commit.
> 3. Fetch only the source commit into a temporary Git repository. Do not clone full history. Derive repository_url from sourceUrl, including repository renames. If sourceCommit is absent, resolve the sourceUrl ref once. Set source_commit to that actual commit. Run these commands in one shell call:
>
> ```sh
> git init --quiet "$temporary_dir"
> git -C "$temporary_dir" fetch --quiet --depth=1 "$repository_url" "$source_commit"
> git -C "$temporary_dir" checkout --quiet --detach FETCH_HEAD
> ```
>
> Read applicable licence declarations and notices at that commit. If copying is not permitted, report the restriction and stop.
> 4. Inspect source entries together, then copy the directory containing skillPath into `./skills/react-doctor`. Use the user's path if selected. Keep the original SKILL.md, relative links, scripts, binary assets, and executable modes. Exclude .git metadata. Reject symlinks and paths outside the Skill directory. After checking entries, use cp -a where available. A regular source directory needs no custom copy script. Do not save this page wrapper as SKILL.md.
> Preserve author credit, notices, and applicable licence files from repository or parent directories. Add PROVENANCE.md with the Skill page, source URL, actual commit, original path, and licence. Retain any existing PROVENANCE.md and record new provenance separately. Batch source inspection, copying, and provenance work where practical.
> 5. In the project root, run `skilld install ./skills/react-doctor --mode copy --plain`. If skilld is unavailable, use `npx skilld install ./skills/react-doctor --mode copy --plain`. This known command needs no help lookup. Install does not support --json. Use detected Agent targets, or add --agent for the targets the user selected. Install the local path, never the upstream selector. If installation fails, preserve the local copy and report the exact failure.
> 6. Confirm the local lockfile source and installed Agent copies once. Report the local path, actual commit, and Agent targets. After edits, reinstall the same local path. Upstream updates must not replace it. Do not publish or push unless the user asks.

# React Doctor

Scans your React codebase for security, performance, correctness, and architecture issues. Outputs a 0-100 score with actionable diagnostics.

## Usage

```bash
npx -y react-doctor@latest . --verbose
```

## Workflow

1. Run the command above at the project root
2. Read every diagnostic with file paths and line numbers
3. Fix issues starting with errors (highest severity)
4. Re-run to verify the score improved

## Rules (47+)

- **Security**: hardcoded secrets in client bundle, eval()
- **State & Effects**: derived state in useEffect, missing cleanup, useState from props, cascading setState
- **Architecture**: components inside components, giant components, inline render functions
- **Performance**: layout property animations, transition-all, large blur values
- **Correctness**: array index as key, conditional rendering bugs
- **Next.js**: missing metadata, client-side fetching for server data, async client components
- **Bundle Size**: barrel imports, full lodash, moment.js, missing code splitting
- **Server**: missing auth in server actions, blocking without after()
- **Accessibility**: missing prefers-reduced-motion
- **Dead Code**: unused files, exports, types

## Score

- **75+**: Great
- **50-74**: Needs work
- **0-49**: Critical