index-beacon

Check which pages of your built static site search engines are told not to index or follow, via meta robots and X-Robots-Tag, against the rules you actually intend.

One stray noindex can remove a money page from Google, and a staging X-Robots-Tag: noindex that ships to production can remove the whole site. The opposite also happens: search result pages, drafts and thank-you pages get indexed. index-beacon reads every built HTML page and the header rules in Netlify/Cloudflare _headers and vercel.json, works out the effective robots directives for each page, and compares them with your intended indexing rules. Each finding has the file, line, severity and a concrete fix.

CLI, library and GitHub Action. Node.js 18+, zero runtime dependencies. Works on any static build output (Astro, Next.js output: 'export', Eleventy, Hugo, Jekyll, Docusaurus, VitePress, plain HTML) and runs offline: point it at the folder your build writes. By Louis Wright.

Features

• Intent: declare which pages should be noindex (noindex globs; sensible defaults such as /search, /admin/**, /drafts/**, /thank-you*, /cart*), which must stay indexable (index globs win), and where nofollow is intended. Everything else is expected to be indexable and followed.
• Leaks: site-wide noindex, from a /* header rule or because every page is noindex (critical).
• Per page: unexpected noindex/none, unexpected nofollow, indexable pages that should be noindex, passed unavailable_after dates.
• Correctness: robots meta outside <head>, contradictory directives (index + noindex, meta vs header), bot-specific rules (googlebot, bingbot, ...) that disagree with the generic one, unknown or misspelt directives (no-index).
• Visibility: nosnippet / max-snippet:0 on indexable pages (hides them from rich results and AI answers) and noimageindex.
• Text/JSON/SARIF/Markdown output, --fail-on, exit codes 0/1/2, allowlist with expiry, severity overrides, GitHub Action with job summary.

Scope

index-beacon looks at meta robots and X-Robots-Tag only. It does not read or lint robots.txt (see securitytxt-sentinel for robots.txt hygiene and answer-beacon for AI-crawler rules), and it does not check sitemaps (sitemap-beacon) or canonicals (canonical-beacon).

Rules

| Rule | Default severity | What it means | |---|---|---| | index-site-wide-noindex | critical | Every page (or a site-wide header rule) is noindex: a staging setting leaked into production | | index-unexpected-noindex | high | Page should be indexable but is noindex (meta robots or X-Robots-Tag) | | index-expired | high | unavailable_after date has passed, so the page is dropped from the index | | index-meta-in-body | high | Robots meta tag is outside and may be ignored | | index-unexpected-indexable | medium | Page should be noindex (matches a noindex rule) but is indexable | | index-unexpected-nofollow | medium | Page should be followed but is nofollow | | index-conflict | medium | Contradictory directives (index + noindex, or meta and header disagree) | | index-bot-differs | low | A bot-specific robots meta (e.g. googlebot, bingbot) disagrees with the generic one | | index-invalid-directive | low | Unknown or malformed robots directive | | index-snippet-restricted | low | Indexable page blocks or limits snippets (nosnippet, max-snippet:0), hiding it from rich results and AI answers | | index-noimageindex | info | Images on the page are excluded from image search | | index-noindex-page | info | Page is noindex as intended | | allowlist-expired | medium | An allowlist entry is past its expires date | | allowlist-unused | info | An allowlist entry matched nothing |

Install and run

npx index-beacon dist
npx index-beacon dist --noindex "/internal/**,/landing/test-*" --fail-on medium
npx index-beacon public --index "/search" --nofollow "/user/**"
npx index-beacon out --no-defaults --report-intended --format markdown

Pages are mapped to URLs the way static hosts serve them: index.html → /, blog/index.html → /blog/, about.html → /about.html (or /about with --clean-urls). Pass --base-url with your public URL, or let it be inferred from canonical / og:url tags. Meta-refresh redirect stubs and 404.html are skipped. X-Robots-Tag and Link headers are read from Netlify/Cloudflare _headers and vercel.json.

Sample output

index-beacon — /workspace/index-beacon/test/fixtures/bad
11 page(s); 5 noindex

HIGH     _headers:1 /hdr.html is noindex via X-Robots-Tag "noindex" (_headers) [index-unexpected-noindex]
         ↳ fix: Remove noindex, or add "/hdr.html" to the "noindex" rules if it is intentional.
HIGH     bot.html:1 /bot.html is noindex via <meta name="googlebot" content="noindex"> [index-unexpected-noindex]
         ↳ fix: Remove noindex, or add "/bot.html" to the "noindex" rules if it is intentional.
HIGH     both.html:1 /both.html is noindex via <meta name="robots" content="noindex"> [index-unexpected-noindex]
         ↳ fix: Remove noindex, or add "/both.html" to the "noindex" rules if it is intentional.
HIGH     docs.html:1 <meta name="robots" content="noindex"> on /docs.html is outside <head> [index-meta-in-body]
         ↳ fix: Move robots meta tags into <head>.
HIGH     docs.html:1 /docs.html is noindex via <meta name="robots" content="noindex"> [index-unexpected-noindex]

Options

index-beacon 1.0.0 — check meta robots and X-Robots-Tag against your intended indexing rules

Usage: index-beacon [site-dir] [options]

Site
      --base-url <url>        Public URL of the site, e.g. https://example.com (default: inferred from canonical/og:url)
      --include <globs>       Only check these pages (file or URL path globs, comma-separated)
      --exclude <globs>       Skip these pages
      --clean-urls            Pages are served without .html (about.html -> /about)
Intended indexing
      --noindex <globs>        Pages that should be noindex (added to the defaults)
      --index <globs>          Pages that must be indexable (wins over --noindex)
      --nofollow <globs>       Pages where nofollow is intended
      --no-defaults            Do not use the built-in noindex globs (/search, /admin/**, /drafts/**, ...)
      --report-intended        Also list intentionally noindex pages (info)

Common
  -c, --config <file>     JSON config (default: .index-beacon.json or "indexBeacon" in package.json)
  -f, --format <fmt>      text (default) | json | sarif | markdown
      --json <file>       Also write a JSON report
      --sarif <file>      Also write SARIF 2.1.0
      --markdown <file>   Also write Markdown (e.g. for a job summary)
      --fail-on <sev>     critical | high | medium | low | info | none (default: high)
      --list-rules        Print rules and default severities
      --no-fixes          Hide fix suggestions in text output
      --no-color          Disable colours
  -v, --version / -h, --help

Exit codes: 0 = passed, 1 = findings at or above --fail-on, 2 = usage, config or read error.

Configuration and allowlist

Options can live in .index-beacon.json (or a "indexBeacon" key in package.json, or --config <file>):

{
  "failOn": "medium",
  "severity": {
    "index-site-wide-noindex": "low"
  },
  "allowlist": [
    {
      "rule": "index-unexpected-noindex",
      "subject": "/beta/*",
      "reason": "Beta section stays out of the index until launch",
      "expires": "2027-03-31"
    }
  ],
  "noindex": [
    "/internal/**"
  ],
  "index": [
    "/search"
  ],
  "nofollow": [
    "/user/**"
  ]
}

• severity changes a rule's severity, or turns it "off".
• allowlist entries suppress matching findings. Each needs a reason and matches on any combination of rule, file, subject (globs with *) and match (a substring of the message). Add expires (YYYY-MM-DD) so the exception is time-boxed: once it lapses the finding comes back along with an allowlist-expired finding (medium). Entries that no longer match anything are reported as allowlist-unused (info).

Config can also set baseUrl, include, exclude and cleanUrls. The config file is looked up in the site directory first, then in the current directory, so .index-beacon.json can live at your repository root. Other keys: noindex, index, nofollow (glob lists), "useDefaults": false, reportIntended and siteWideMin (minimum pages before the all-noindex check fires, default 3). Globs match the URL path (/blog/**) or the file (blog/*.html).

Output and exit codes

• --format text (default), json, sarif (SARIF 2.1.0 for GitHub code scanning) or markdown (for job summaries and PR comments). --json, --sarif and --markdown write extra report files in the same run.
• --fail-on <severity> sets the threshold (critical, high, medium, low, info, none; default high).
• Exit codes: 0 passed, 1 findings at or above --fail-on, 2 usage, config or read error.

GitHub Action

permissions:
  contents: read
  security-events: write   # only needed for the SARIF upload
jobs:
  index-beacon:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
        with: { persist-credentials: false }
      - run: npm ci && npm run build   # produce the static site first
      - uses: MrLouisWright/index-beacon@v1
        with:
          path: dist
          fail-on: high
          sarif: index-beacon.sarif
      - uses: github/codeql-action/upload-sarif@v3
        if: always()
        with: { sarif_file: index-beacon.sarif }

| Input | Description | Default | |---|---|---| | path | Built site directory (e.g. dist, public, _site) | . | | base-url | Public URL of the site, e.g. https://example.com | | | fail-on | Failure threshold | high | | config | Config file path | | | sarif / json | Write SARIF / JSON report to this path | | | job-summary | Add the Markdown report to the job summary | true | | args | Extra CLI arguments | |

The action runs the bundled CLI with Node 20; it has no dependencies to install. Pin it to a commit SHA if your policy requires it.

Library

import { check, DEFAULT_NOINDEX } from "index-beacon";
const report = check("dist", { noindex: ["/internal/**"], index: ["/search"] });
console.log(report.info.noindex, report.findings);

Types are included.

Requirements

Node.js 18 or newer. Zero runtime dependencies.

Support

If this project is useful to you, you can support its development with a donation: Buy me a coffee. It helps keep these tools maintained, documented and free for everyone.

Credit (optional)

Free to use under MIT, no attribution required. If index-beacon helps you, a link back is appreciated:

<a href="https://louiswright.co.uk">Built with index-beacon by Louis Wright</a>

[![Built with index-beacon by Louis Wright](https://img.shields.io/badge/built%20with-index--beacon-blue)](https://louiswright.co.uk)

Licence

MIT © Louis Wright (Louis Wright)