# Sitemap Valid > Use when applies to any site with a manually or programmatically generated XML sitemap. Use when debugging sitemap submission errors in Google Search Console. - Skill: `thedaviddias/sitemap-valid` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add thedaviddias/sitemap-valid` - Raw SKILL.md: https://api.skillmd.com/api/skills/thedaviddias/sitemap-valid/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: thedaviddias (https://skillmd.com/u/thedaviddias) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/thedaviddias/sitemap-valid --- # Keep XML sitemaps valid An invalid or malformed sitemap is silently ignored by search engines, leaving newly published or orphaned pages undiscovered by crawlers. ## Quick Reference - The root element must be `` with the correct `xmlns` namespace - Each `` must contain exactly one `` element with a fully qualified, percent-encoded URL - Maximum 50,000 URLs and 50 MB per sitemap file; use a sitemap index for larger sites - Encode XML special characters: `&` → `&`, `<` → `<`, `>` → `>`, `"` → `"`, `'` → `'` ## Check Fetch the sitemap and validate it against the sitemaps.org schema. Check that the `xmlns` attribute is `http://www.sitemaps.org/schemas/sitemap/0.9`, all `` values are absolute URLs, no file exceeds 50,000 URLs or 50 MB, and special characters are properly XML-encoded. ## Fix Re-generate the sitemap using a validated sitemap library. Encode all special characters in URLs (`&` → `&`). Split oversized sitemaps into multiple files and reference them from a sitemap index. Resubmit to Google Search Console. ## Explain Explain the sitemaps.org XML schema requirements, what causes validation errors in Google Search Console, and how encoding errors in `` URLs prevent crawlers from fetching those pages. ## Code Review Review metadata generation, rendered HTML, structured data, and response headers related to Keep XML sitemaps valid. Flag exact routes or templates where search-facing output violates the rule, and describe how to verify the final page output. --- For full implementation details, code examples, and framework-specific guidance, see `references/rule.md`. Rule page: https://frontendchecklist.io/en/rules/seo/sitemap-valid