Hreflang and international SEO audit, validation, and generation. Detects common mistakes, validates language/region codes, and generates correct hreflang implementations. Use when user says "hreflang", "i18n SEO", "international SEO", "multi-language", "multi-region", or "language tags".
Installation
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Hreflang and international SEO audit, validation, and generation. Detects common mistakes, validates language/region codes, and generates correct hreflang implementations. Use when user says "hreflang", "i18n SEO", "international SEO", "multi-language", "multi-region", or "language tags".
allowed-tools
["WebFetch","Read"]
Hreflang & International SEO
Validate existing hreflang implementations or generate correct hreflang tags
for multi-language and multi-region sites. Supports HTML, HTTP header, and
XML sitemap implementations.
Validation Checks
1. Self-Referencing Tags
Every page must include an hreflang tag pointing to itself
The self-referencing URL must exactly match the page's canonical URL
Missing self-referencing tags cause Google to ignore the entire hreflang set
2. Return Tags
If page A links to page B with hreflang, page B must link back to page A
Every hreflang relationship must be bidirectional (A→B and B→A)
Missing return tags invalidate the hreflang signal for both pages
Check all language versions reference each other (full mesh)
3. x-default Tag
Required: designates the fallback page for unmatched languages/regions
Typically points to the language selector page or English version
Only one x-default per set of alternates
Must also have return tags from all other language versions
4. Language Code Validation
Must use ISO 639-1 two-letter codes (e.g., en, fr, de, ja)
Common errors:
eng instead of en (ISO 639-2, not valid for hreflang)
jp instead of ja (incorrect code for Japanese)
zh without region qualifier (ambiguous — use zh-Hans or zh-Hant)
5. Region Code Validation
Optional region qualifier uses ISO 3166-1 Alpha-2 (e.g., en-US, en-GB, pt-BR)
