Robots Txt Audit

Robots.txt Audit

Audit a website's robots.txt file and produce an actionable SEO report.

When to use this skill

Use this skill when the user asks to:

• Audit, validate, or check a robots.txt file or crawl directives
• Find out why pages are not being crawled or why Google says a URL is "blocked by robots.txt"
• Check that important pages aren't blocked and that CSS/JS resources can be rendered
• Confirm robots.txt declares the XML sitemap and returns 200 as plain text
• Catch a stray Disallow: / that took the whole site out of search
• Clean up syntax errors and unsupported directives (noindex, crawl-delay, etc.)

Inputs to collect

Before starting, confirm with the user:

1. Site URL or robots.txt URL — a live site root (e.g., https://example.com, which fetches /robots.txt) or a specific robots.txt URL (--robots).
2. Resource check — whether to fetch the homepage and test its CSS/JS/image references against the rules (default on). Use --no-resources to skip it.

> What robots.txt does and does not do: robots.txt controls crawling, not indexing. A Disallow stops compliant crawlers from fetching a page, but a blocked URL can still be indexed (without a snippet) if other pages link to it. To keep a page out of the index, allow crawling and use a noindex meta tag or X-Robots-Tag header instead — noindex inside robots.txt is unsupported and ignored. Most checks here protect crawl access and rendering rather than indexing.

Workflow

Step 1: Fetch and parse robots.txt

Use scripts/collect_robots.py:

python3 scripts/collect_robots.py https://example.com --output robots_inventory.json

Point directly at a robots.txt with --robots:

python3 scripts/collect_robots.py https://example.com/robots.txt --robots --output robots_inventory.json

The script fetches /robots.txt without auto-following redirects (so a redirected or HTML-served file is visible), records HTTP status, content type, byte size, gzip, and a BOM flag, then parses user-agent groups, Sitemap: directives, comments, unknown/unsupported directives, and per-line syntax errors. It probes every declared sitemap URL for status and (unless --no-resources) fetches the homepage to test same-host CSS/JS/image references against the * group's rules.

Step 2: Run the audit checks

Use scripts/audit_robots.py:

python3 scripts/audit_robots.py robots_inventory.json --output audit_report.json

Step 3: Evaluate the audit checks

Evaluate each check defined in references/audit-checks.md. The core checks are:

| Check | Severity | |---|---| | robots.txt returns 5xx (read as "block everything") | High | | robots.txt redirects instead of returning the file | High | | robots.txt served as HTML, not plain text | High | | Sitewide Disallow: / blocks the whole site | High | | Syntax error / directive before any User-agent | High | | File exceeds 500 KiB | High | | Render-critical CSS/JS blocked from crawling | Medium | | No Sitemap: directive | Medium | | Declared Sitemap: URL unreachable or not absolute | Medium | | No default User-agent: * group | Medium | | Unsupported directive (noindex, nofollow, crawl-delay) | Medium | | robots.txt missing entirely (404) | Low | | Duplicate User-agent: * group | Low | | UTF-8 BOM precedes the file | Low | | Empty Disallow: alongside real rules | Low |

Step 4: Produce the report

Write a report following the structure in references/report-template.md:

1. Summary — fetch status, group count, sitemaps declared, issue counts by severity
2. Fetch & file — status, content type, size, redirect/HTML/BOM flags
3. Issues — one section per failing check, with the offending directive/line and the fix
4. Prioritized action list — ordered by severity and impact

Step 5: Recommend fixes

For each issue, give a concrete fix:

• 5xx / redirect / HTML: serve robots.txt from the root path as text/plain returning 200 directly (no redirect, no HTML error page). A persistent 5xx will pause crawling site-wide.
• Sitewide Disallow: /: confirm it is intentional (it usually is not on a production site) and remove or scope it; this single line can deindex an entire domain.
• Syntax errors: fix malformed lines — every directive needs field: value, and Disallow/Allow must follow a User-agent line.
• Blocked resources: add Allow: rules (or remove the Disallow) so Googlebot can fetch the CSS/JS it needs to render the page.
• Sitemap directive: add an absolute Sitemap: line for each sitemap (or the index); fix any that 404.
• Unsupported directives: remove noindex/nofollow from robots.txt and enforce them via meta robots or X-Robots-Tag; drop crawl-delay (Google ignores it — set the rate in Search Console if needed).
• Base every recommendation on the observed file; quote the exact line to change and do not invent rules.

Optional: export the report

As a Word document (.docx)

If the user wants the report as a .docx (for example, to share with stakeholders or attach to a ticket), save the Markdown report to a file and convert it:

python3 scripts/md_to_docx.py report.md --output report.docx

scripts/md_to_docx.py uses only the Python standard library (no pip install) and renders headings, tables, lists, links, bold/italic, and code blocks. Offer this whenever a user asks for a Word doc, a .docx, or a shareable/downloadable report.

As a CSV of findings (.csv)

If the user wants the raw findings as a spreadsheet (for filtering, sorting, or triage in Sheets or Excel), convert the audit's audit_report.json directly:

python3 scripts/findings_to_csv.py audit_report.json --output findings.csv

scripts/findings_to_csv.py is also standard-library only. It writes one row per finding, with check and severity columns prepended and list fields (e.g. the pages sharing a duplicate value) joined with ; . Unlike the .docx, which reformats the written report, the CSV is a direct dump of the structured findings — offer it whenever a user wants the data itself, a spreadsheet, or to slice findings by check or severity.

Resources

• scripts/md_to_docx.py — convert the Markdown report into a Word (.docx) document (standard library only)
• scripts/findings_to_csv.py — flatten the audit findings JSON into a CSV, one row per finding (standard library only)
• references/audit-checks.md — full definitions, thresholds, and rationale for every audit check
• references/report-template.md — report output structure
• scripts/collect_robots.py — fetch, parse, and probe a site's robots.txt
• scripts/audit_robots.py — run audit checks against a robots.txt inventory JSON file

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: JakeLabate
• Source: JakeLabate/Claude-SEO-Skills
• License: MIT
• Homepage: https://www.jakelabate.com/claude-seo-skills/

Install and usage instructions live in the source repository linked above.