Automatic SEO

biagiojs generates all SEO markup at build time. No plugin, no hand-written meta tags per page.

What gets generated

Per page, automatically:

• <title> and meta description
• rel="canonical"
• Open Graph (og:title, og:description, og:image, og:url)
• Twitter Card
• JSON-LD (Organization, WebSite, SoftwareApplication, TechArticle, BreadcrumbList)
• hreflang (when site.locales is set)
• og:locale as en_US / it_IT (Open Graph format)
• Favicon link

Site-wide:

• sitemap.xml with priority, lastmod and xhtml:link hreflang alternates
• robots.txt pointing to the sitemap
• /llms.txt — curated index for AI agents (spec)

Page configuration

In .biagio:

<page title="Product X — My Shop"
      description="Description for search engines."
      type="product"
      image="/img/product-960w.jpg"
      sitemapPriority="0.9"
      lastmod="2026-07-07" />

In .page.js:

page: {
  title: 'Page title',
  description: '…',
  type: 'product',
  image: '/img/hero-960w.jpg',
  product: { name: 'X', price: 129, currency: 'EUR', rating: 4.7, reviewCount: 100 },
  breadcrumbs: [{ name: 'Home', path: '/' }, { name: 'Shop', path: '/shop/' }],
}

Open Graph image

Use a PNG or JPEG at 1200×630 for site.ogImage — social networks do not reliably render SVG.

site: {
  ogImage: { src: '/og.png', width: 1200, height: 630, alt: '…' },
}

Duplicate breadcrumbs

If your layout renders its own breadcrumb, set hideBreadcrumb: true on page — JSON-LD BreadcrumbList is still emitted.

hreflang (i18n)

With site.locales: ['en', 'it'] and defaultLocale: 'en':

• Default locale at /, others at /<lang>/…
• hreflang alternate links on every page
• Sitemap with xhtml:link per language
• Per-market optimizer reports in reports/it/

This documentation site is bilingual: English at /, Italian at /it/ — hreflang is generated automatically.

Images and LCP

Use smartImage() with aboveFold: true and hero profile for LCP. The pipeline generates AVIF/WebP/JPEG with correct srcset.

Favicon generator (opt-in)

Point site.favicon at a single source and biagiojs builds the modern essential set at build time — no legacy 20-file dump:

// biagio.config.js
site: {
  favicon: {
    source: 'images/logo.svg',   // SVG ideal, or PNG ≥512
    generate: true,              // opt-in
    themeColor: '#111',
    // targets: ['ico', 'svg', 'apple', 'pwa'],  // opt out of what you don't need
  },
}

Outputs written to dist/:

The <link>/<meta> tags (including rel="manifest" and theme-color) are injected automatically. Raster targets (ico, apple, pwa) require sharp; biagio doctor warns if it's missing or the source is too small. Generation is idempotent — it skips when outputs are newer than the source.

noindex

noindex: true excludes the page from sitemap.xml.

baseUrl

Required in production.site.baseUrl feeds canonical, OG url and sitemap. A placeholder triggers a warning in biagio doctor.

The official docs site uses https://biagio.danilosprovieri.com — every page gets that canonical automatically at build time.

Submit https://biagio.danilosprovieri.com/sitemap.xml in Google Search Console after deploy. See also AI agents for llms.txt.