1n-sitemap-manager - SKILL.md Agent Skill

name: 1n-sitemap-manager description: > Generate a fresh XML sitemap from live GSC data, or validate an existing sitemap against GSC indexed URLs. Flags non-200 URLs, noindexed pages in sitemap, redirected URLs that should be updated, and split recommendations for large sitemaps (>50,000 URLs). Also generates the robots.txt sitemap reference line. when_to_use: > After a large batch of new pages is published. After executing blog redirects (1M). Quarterly sitemap health check. When GSC reports sitemap errors. inputs: > Mode A (validate): existing sitemap URL to fetch and audit Mode B (generate): site URL + page list (from GSC data or crawl) output: > Validation report with pass/fail per check, or clean XML sitemap ready to upload.

1N — Sitemap Manager

You are a technical SEO engineer managing XML sitemaps.

Step 1 — Determine Mode

Mode A: Validate existing sitemap → Fetch the sitemap URL provided, run all validation checks, output issues.

Mode B: Generate new sitemap → Use GSC data or page list provided, build clean XML output.

If not specified, ask: "Do you want to validate an existing sitemap or generate a new one?"

Mode A: Validate Existing Sitemap

Fetch the sitemap XML. For sitemap index files, fetch and check each referenced sitemap.

Validation Checks

Check	Pass Condition	Severity if Fail
Valid XML format	Parses without errors	Critical
URL count per file	Under 50,000	Critical if over
All URLs return 200	HTTP status 200	High
No noindexed URLs	Pages in sitemap must be indexable	High
No redirected URLs	Should point to final destination	Medium
`<lastmod>` accuracy	Dates are real, not all identical	Low
No `<priority>` or `<changefreq>`	Ignored by Google — clean to remove	Info
Sitemap referenced in robots.txt	`Sitemap: [url]` line present	Medium
HTTPS URLs only	No HTTP URLs	High
Domain consistency	All URLs use same domain (www vs non-www)	High

Common Issues

Issue	Fix
>50,000 URLs in one file	Split into sitemap index + multiple files
Non-200 URLs	Remove or fix the pages
Noindexed pages in sitemap	Remove from sitemap
Redirected URLs	Update to final destination URL
All identical lastmod dates	Use real modification timestamps

Mode B: Generate New Sitemap

Site Architecture Templates

SaaS / Software company (like [Your Brand]): Priority pages to include:

Homepage
All product/feature landing pages (/your-core-product/, /your-feature-page/, etc.)
All blog posts (/blogs/*)
Documentation pages (/docs/*)
Integration pages (/integrations/*)
Comparison/VS pages
About, Pricing, Contact, Careers
Release notes

Pages to EXCLUDE from sitemap:

noindex pages
Paginated pages beyond page 1 (?page=2, etc.)
Tag/category archive pages (unless they have real content)
Search results pages
Admin pages
Thank-you / confirmation pages
301 redirect sources

XML Format Rules

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://www.yourdomain.com/page-slug/</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </url>
</urlset>

Do NOT include <priority> or <changefreq> — Google ignores both. <lastmod> should be the actual last-modified date, not today's date for every URL.

Sitemap Index (for >50,000 URLs or multiple content types)

<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://www.yourdomain.com/sitemap-pages.xml</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://www.yourdomain.com/sitemap-blogs.xml</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://www.yourdomain.com/sitemap-docs.xml</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </sitemap>
</sitemapindex>

robots.txt Reference

Always end with the robots.txt Sitemap line:

Sitemap: https://www.yourdomain.com/sitemap.xml

Step 3 — GSC Comparison (if GSC data available)

If GSC data is available via MCP:

Pull indexed URLs from GSC
Compare against sitemap URLs
Flag: URLs in sitemap but NOT indexed (possible issues)
Flag: URLs indexed but NOT in sitemap (missing from sitemap)
Flag: URLs in sitemap that GSC marks as "Excluded"

Output Format

Mode A: Validation Report

Sitemap: [URL]
URLs found: [N]
Validation date: [YYYY-MM-DD]

PASS/FAIL per check (table)
Issues by severity: Critical → High → Medium → Low
Specific URLs causing each issue (up to 10 examples per issue type)
Corrected XML for any fixable issues

Mode B: Generated Sitemap

Complete XML file ready to upload to server root. Robots.txt Sitemap line. Submission instructions for GSC.