Your agent writes bad React, this catches it.

React Doctor deterministically scans your codebase and finds issues across state & effects, performance, architecture, security, and accessibility.

Works for all React frameworks and libraries - Next.js, Vite, TanStack, React Native, Expo, you name it.

Website →

Run this at your project root to get an audit.

npx react-doctor@latest

Once you have an audit, you can install the skill for your coding agent to learn from the issues and fix them in the future.

npx react-doctor@latest install

Works with Claude Code, Cursor, Codex, OpenCode, and many more.

React Doctor ships an experimental language server, so diagnostics show up live as you type — underlined inline, with rich hovers and quick fixes — in VS Code, Cursor, Zed, Neovim, Sublime, Emacs, Helix, or any LSP client. The universal launch command is:

react-doctor experimental-lsp --stdio

The editor language server is experimental — its protocol, caching, and diagnostics may change between releases, hence the experimental- prefix.

Companion extensions for VS Code/Cursor and Zed live under packages/; any other LSP client can run the command above directly over stdio.

On a pull request the Action reports only the issues your change introduced — it scans the PR and the merge-base and reports the difference (like Codecov for coverage), leaving pre-existing findings alone. It posts inline review comments on the changed lines and a sticky summary with the new / fixed delta.

name: React Doctor

on:
  pull_request:
    types: [opened, synchronize, reopened, ready_for_review]

permissions:
  contents: read
  pull-requests: write
  issues: write

concurrency:
  group: react-doctor-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: true

jobs:
  react-doctor:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
        with:
          fetch-depth: 0 # so React Doctor can diff against the merge-base for new-vs-existing
      - uses: millionco/react-doctor@v1

fetch-depth: 0 is recommended so the baseline comparison can read the base commit; without enough history the Action falls back to reporting every finding in the changed files.

@v1 always resolves to the latest v1.x release of the Action. For hardened CI — recommended whenever the workflow is granted pull-requests: write — pin to a full commit SHA instead and let Dependabot or Renovate keep it current:

- uses: millionco/react-doctor@b612664043a9be414166e3c6a69b355e39a8dcf4 # v1.1.1

Add GitHub Action →

Configure with a doctor.config.ts (or .js, .mjs, .cjs, .json, .jsonc) in your project root.

// doctor.config.ts
import type { ReactDoctorConfig } from "react-doctor/api";

export default {
  lint: true,
  rules: {
    "react-doctor/no-array-index-as-key": "off",
  },
} satisfies ReactDoctorConfig;

Prefer JSON? Use doctor.config.json:

{
  "$schema": "https://react.doctor/schema/config.json",
  "lint": true,
}

The CLI reports crashes, basic run traces, and anonymous usage counters to Sentry to help us fix bugs and prioritize work.

We collect:

• Environment: CLI version, platform, Node version
• Invocation: which command, package manager, and run context (whether it's local vs. CI vs. coding agent)
• Project shape: framework, React version, TypeScript, project size NO file contents)
• Rules fired: rule names and counts only (e.g. react-doctor/no-array-index-as-key) (NO code or specific findings)
• De-minified React Doctor CLI stack traces

To opt out, run: npx react-doctor@latest --no-telemetry

Issues welcome!

MIT-licensed