- Skill ID
- agricidaniel/claude-seo/seo-hreflang
- Publisher
- agricidaniel
- Repository
- claude-seo
- Installs
- 0
- Files
- 6
- License
- MIT
- Synced
- Sep 23, 2026
Open any RiverX project, open the Skills panel in the chat, and search for this identifier. The files are fetched from the source repository at install time.
agricidaniel/claude-seo/seo-hreflangInstalls these files- LICENSE.txt
- SKILL.md
- references/content-parity.md
- references/cultural-profiles.md
- references/locale-formats.md
- references/machine-translation-qa.md
What this skill tells the agent
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
- Recommended when a selector/fallback URL exists: 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) - An optional ISO 15924 script subtag is the documented, official mechanism for script:
zh-Hant(Traditional) /zh-Hans(Simplified). Script may combine with a region, e.g.zh-Hans-USis valid (language + script + region). - Common errors:
enginstead ofen(ISO 639-2, not valid for hreflang)jpinstead ofja(incorrect code for Japanese)zhis valid but ambiguous for script-specific pages; preferzh-Hansorzh-Hantwhen targeting a script
5. Region Code Validation
- Optional region qualifier uses ISO 3166-1 Alpha-2 (e.g.,
en-US,en-GB,pt-BR) - Format:
language-REGION(lowercase language, uppercase region) - A country code alone is invalid, you cannot specify a region without a language (Google's own bad example is
be, which is actually the Belarusian language code, not Belgium). - Common errors:
en-ukinstead ofen-GB(UK is not a valid ISO 3166-1 region code)EU/UNas a region (not valid ISO 3166-1 values)es-LA(Latin America is not a country; use specific countries)- Region without language prefix
5b. Geo-targeting signal hierarchy
- Practical locale-signal heuristic: ccTLD > hreflang annotations > server location/IP > addresses/language/currency/Business Profile. Do not present this as a confirmed Google ranking order. hreflang is a hint, not a directive. Google ignores locational meta tags and HTML geotargeting attributes.
- The Search Console International Targeting report and the manual country-targeting setting were removed in 2022, do not recommend setting country targeting in GSC; hreflang is the remaining lever.
5c. Region-specific Search units (EEA, South Africa, Turkiye)
- Google documents Search experiences that exist only in certain countries: aggregator units, supplier units, and carousels for hotel, flight, long-distance transport, and product queries shown to users in the EEA, South Africa, and Turkiye (documentation added 2026-09-08). Eligibility and participation are documented per unit; they are not ranking signals.
- When a site serves those regions with hreflang variants, note in the report whether the business is an aggregator or a direct supplier and point to the regional documentation, so the client is not surprised by a different result layout in those markets.
6. Canonical URL Alignment
- Hreflang tags must only appear on canonical URLs
- If a page has
rel=canonicalpointing elsewhere, hreflang on that page is ignored - The canonical URL and hreflang URL must match exactly (including trailing slashes)
- Non-canonical pages should not be in any hreflang set
7. Protocol Consistency
- All URLs in an hreflang set must use the same protocol (HTTPS or HTTP)
- Mixed HTTP/HTTPS in hreflang sets causes validation failures
- After HTTPS migration, update all hreflang tags to HTTPS
8. Cross-Domain Support
- Hreflang works across different domains (e.g., example.com and example.de)
- Cross-domain hreflang requires return tags on both domains
- Use Google Search Console verification for monitoring or cross-site sitemap submission when needed
- Sitemap-based implementation recommended for cross-domain setups
Common Mistakes
| Issue | Severity | Fix |
|---|---|---|
| Missing self-referencing tag | Critical | Add hreflang pointing to same page URL |
| Missing return tags (A→B but no B→A) | Critical | Add matching return tags on all alternates |
| Missing x-default when fallback behavior is required | Medium | Add x-default pointing to fallback/selector page |
Invalid language code (e.g., eng) | High | Use ISO 639-1 two-letter codes |
Invalid region code (e.g., en-uk) | High | Use ISO 3166-1 Alpha-2 codes |
| Hreflang on non-canonical URL | High | Move hreflang to canonical URL only |
| HTTP/HTTPS mismatch in URLs | Medium | Standardize all URLs to HTTPS |
| Trailing slash inconsistency | Medium | Match canonical URL format exactly |
| Hreflang in both HTML and sitemap | Low | Choose one method (sitemap preferred for large sites) |
| Language without region when needed | Low | Add region qualifier for geo-targeted content |
Implementation Methods
Method 1: HTML Link Tags
Best for: Sites with <50 language/region variants per page.
<link rel="alternate" hreflang="en-US" href="https://example.com/page" />
<link rel="alternate" hreflang="en-GB" href="https://example.co.uk/page" />
<link rel="alternate" hreflang="fr" href="https://example.com/fr/page" />
<link rel="alternate" hreflang="x-default" href="https://example.com/page" />Place in <head> section. Every page must include all alternates including itself.
Method 2: HTTP Headers
Best for: Non-HTML files (PDFs, documents).
Link: <https://example.com/page>; rel="alternate"; hreflang="en-US",
<https://example.com/fr/page>; rel="alternate"; hreflang="fr",
<https://example.com/page>; rel="alternate"; hreflang="x-default"Set via server configuration or CDN rules.
Method 3: XML Sitemap (Recommended for large sites)
Best for: Sites with many language variants, cross-domain setups, or 50+ pages.
See Hreflang Sitemap Generation section below.
Method Comparison
| Method | Best For | Pros | Cons |
|---|---|---|---|
| HTML link tags | Small sites (<50 variants) | Easy to implement, visible in source | Bloats <head>, hard to maintain at scale |
| HTTP headers | Non-HTML files | Works for PDFs, images | Complex server config, not visible in HTML |
| XML sitemap | Large sites, cross-domain | Scalable, centralized management | Not visible on page, requires sitemap maintenance |
Hreflang Generation
Process
- Detect languages: Scan site for language indicators (URL path, subdomain, TLD, HTML lang attribute)
- Map page equivalents: Match corresponding pages across languages/regions
- Validate language codes: Verify all codes against ISO 639-1 and ISO 3166-1
- Generate tags: Create hreflang tags for each page including self-referencing
- Verify return tags: Confirm all relationships are bidirectional
- Add x-default: Set fallback for each page set
- Output: Generate implementation code (HTML, HTTP headers, or sitemap XML)
Hreflang Sitemap Generation
Sitemap with Hreflang
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
xmlns:xhtml="http://www.w3.org/1999/xhtml">
<url>
<loc>https://example.com/page</loc>
<xhtml:link rel="alternate" hreflang="en-US" href="https://example.com/page" />
<xhtml:link rel="alternate" hreflang="fr" href="https://example.com/fr/page" />
<xhtml:link rel="alternate" hreflang="de" href="https://example.de/page" />More from agricidaniel
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