Seo hreflang

Skill fusengine/agents/plugins/seo/skills/seo-hreflang

Use when auditing or generating hreflang for i18n SEO. Covers HTML link tags, HTTP headers, XML sitemap hreflang, self-referencing, return tags, x-default, ISO 639-1 + ISO 3166-1 code validation.From its SKILL.md

Install

npx -y skills add fusengine/agents --skill seo-hreflang

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

One thing to look at

22 stars22 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.

SKILL.md

1.3 KB, 297 tokens by cl100k_base, as published. Nobody here has run it

Hreflang / i18n SEO

Workflow

Detect hreflang tags (HTML <link>, HTTP header, or XML sitemap)
Run scripts/parse-hreflang.ts → validate
Check self-referencing, return tags, x-default
Verify language/region codes (ISO 639-1 + ISO 3166-1)

Common Mistakes

❌ Missing self-reference (<link rel="alternate" hreflang="fr" href="/fr/"> from /fr/)
❌ Missing return tags (A → B but not B → A)
❌ Invalid codes (en-UK instead of en-GB)
❌ HTTP/HTTPS mismatch between alternates
❌ Mixing trailing slashes

Implementation Options

HTML head: <link rel="alternate" hreflang="fr-FR" href="https://example.com/fr/">
HTTP Header: Link: <https://example.com/fr/>; rel="alternate"; hreflang="fr-FR"
XML Sitemap: <xhtml:link rel="alternate" hreflang="fr-FR" href="https://example.com/fr/"/>

x-default

Required for international landing/locale selector pages:

<link rel="alternate" hreflang="x-default" href="https://example.com/">

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.