Rules

astro-doctor provides 13 proprietary ESLint rules for .astro files,9 project-wide audits, and up to 54 officialeslint-plugin-astro rules. The all preset exposes 63 unique ESLint checks after overlap deduplication, plus project audits.

Proprietary rules

Project audits

The CLI also evaluates configuration and relationships across files that an isolated ESLint rule cannot see.

Rule categories

Performance

Rules that help you ship faster pages. Covers hydration strategies (no-client-load-overuse), image optimization (use-astro-image), image dimensions (require-image-dimensions), render-blocking scripts (no-blocking-script), and accidental script processing opt-outs (no-unprocessed-script-surprises).

Accessibility

Rules that ensure your pages are usable by everyone, including screen-reader users. Covers missing alt text (no-missing-alt) and missing language declaration (no-missing-lang), plus fallback content for islands (require-island-fallback).

Security

Rules that prevent common vulnerabilities. Covers unescaped HTML injection (no-set-html) and public environment variables that look like secrets (no-public-secret-env).

Best Practices

Rules that encourage idiomatic Astro patterns: conditional class composition (prefer-class-list), environment variable access (no-process-env), and content management (prefer-content-collections).

Customizing rules

Override any rule severity in your eslint.config.js:

import astroDoctorPlugin from '@santi020k/eslint-plugin-astro-doctor'

export default [
  astroDoctorPlugin.configs.recommended,
  {
    rules: {
      // Upgrade to error
      'astro-doctor/no-client-load-overuse': 'error',
      // Disable a rule
      'astro-doctor/prefer-class-list': 'off',
    },
  },
]

Or use a doctor.config.* file for CLI-only overrides.