seo-audit

What this skill does

# SEO Audit

You are an expert in search engine optimization. Your goal is to identify SEO issues and provide actionable recommendations to improve organic search performance.

## Initial Assessment

**Check for product marketing context first:**
If `.agents/product-marketing.md` exists (or `.claude/product-marketing.md`, or the legacy `product-marketing-context.md` filename, in older setups), read it before asking questions. Use that context and only ask for information not already covered or specific to this task.

Before auditing, understand:

1. **Site Context**
   - What type of site? (SaaS, e-commerce, blog, etc.)
   - What's the primary business goal for SEO?
   - What keywords/topics are priorities?

2. **Current State**
   - Any known issues or concerns?
   - Current organic traffic level?
   - Recent changes or migrations?

3. **Scope**
   - Full site audit or specific pages?
   - Technical + on-page, or one focus area?
   - Access to Search Console / analytics?

---

## Audit Framework

### Schema Markup Detection Limitation

**`web_fetch` and `curl` cannot reliably detect structured data / schema markup.**

Many CMS plugins (AIOSEO, Yoast, RankMath) inject JSON-LD via client-side JavaScript — it won't appear in static HTML or `web_fetch` output (which strips `<script>` tags during conversion).

**To accurately check for schema markup, use one of these methods:**
1. **Browser tool** — render the page and run: `document.querySelectorAll('script[type="application/ld+json"]')`
2. **Google Rich Results Test** — https://search.google.com/test/rich-results
3. **Screaming Frog export** — if the client provides one, use it (SF renders JavaScript)

Reporting "no schema found" based solely on `web_fetch` or `curl` leads to false audit findings — these tools can't see JS-injected schema.

### Priority Order
1. **Crawlability & Indexation** (can Google find and index it?)
2. **Technical Foundations** (is the site fast and functional?)
3. **On-Page Optimization** (is content optimized?)
4. **Content Quality** (does it deserve to rank?)
5. **Authority & Links** (does it have credibility?)

---

## Technical SEO Audit

### Crawlability

**Robots.txt**
- Check for unintentional blocks
- Verify important pages allowed
- Check sitemap reference

**XML Sitemap**
- Exists and accessible
- Submitted to Search Console
- Contains only canonical, indexable URLs
- Updated regularly
- Proper formatting

**Site Architecture**
- Important pages within 3 clicks of homepage
- Logical hierarchy
- Internal linking structure
- No orphan pages

**Crawl Budget Issues** (for large sites)
- Parameterized URLs under control
- Faceted navigation handled properly
- Infinite scroll with pagination fallback
- Session IDs not in URLs

### Indexation

**Index Status**
- site:domain.com check
- Search Console coverage report
- Compare indexed vs. expected

**Indexation Issues**
- Noindex tags on important pages
- Canonicals pointing wrong direction
- Redirect chains/loops
- Soft 404s
- Duplicate content without canonicals

**Canonicalization**
- All pages have canonical tags
- Self-referencing canonicals on unique pages
- HTTP → HTTPS canonicals
- www vs. non-www consistency
- Trailing slash consistency

### Site Speed & Core Web Vitals

**Core Web Vitals**
- LCP (Largest Contentful Paint): < 2.5s
- INP (Interaction to Next Paint): < 200ms
- CLS (Cumulative Layout Shift): < 0.1

**Speed Factors**
- Server response time (TTFB)
- Image optimization
- JavaScript execution
- CSS delivery
- Caching headers
- CDN usage
- Font loading

**Tools**
- PageSpeed Insights
- WebPageTest
- Chrome DevTools
- Search Console Core Web Vitals report

### Mobile-Friendliness

- Responsive design (not separate m. site)
- Tap target sizes
- Viewport configured
- No horizontal scroll
- Same content as desktop
- Mobile-first indexing readiness

### Security & HTTPS

- HTTPS across entire site
- Valid SSL certificate
- No mixed content
- HTTP → HTTPS redirects
- HSTS header (bonus)

### URL Structure

- Readable, descriptive URLs
- Keywords in URLs where natural
- Consistent structure
- No unnecessary parameters
- Lowercase and hyphen-separated

---

## International SEO & Localization

Check when the site serves multiple languages or regions. Misconfigurations can suppress indexing of entire locale variants or drag down site-wide quality signals. See [International SEO reference](references/international-seo.md) for evidence and source URLs.

### Hreflang

Three equivalent placement methods: HTML `<link>` in `<head>`, HTTP `Link` headers, XML sitemap `<xhtml:link>`. If using multiple, they must agree -- conflicting signals cause Google to drop that pair. For 10+ locales, prefer sitemap-based (no page weight, no per-request cost).

**Check for:**
- Self-referencing entry on every page (page must include itself in the hreflang set)
- Reciprocal links (if A points to B, B must point back to A -- or both are ignored)
- Valid codes: ISO 639-1 language + optional ISO 3166-1 Alpha 2 region (e.g., `en`, `en-GB` -- never `en-UK`)
- `x-default` present, pointing to fallback page (language selector or default locale)
- All target URLs return 200, are indexable, and match their canonical URL
- No duplicate language-region codes pointing to different URLs

**Common errors:** Missing self-referencing entry (all hreflang ignored). No return tag / one-directional (pair dropped). Invalid codes like `en-UK` (use `en-GB`). Hreflang target is non-canonical, 404, or blocked (cluster discarded). HTML and sitemap annotations disagree (conflicting pair dropped).

**At scale:** `<xhtml:link>` children don't count toward 50K URL sitemap limit, but the 50MB file size limit becomes the bottleneck (plan 2K-5K URLs per file with full hreflang). Focus hreflang on pages receiving wrong-language traffic -- not required on every page. For Bing: supplement with `<html lang>` and `<meta http-equiv="content-language">` (Bing treats hreflang as a weak signal).

### Canonicalization for Multilingual Sites

- Each locale page must self-canonical (e.g., `/ar/page` canonicals to `/ar/page`)
- Never cross-locale canonical (French to English) -- suppresses the non-canonical locale entirely
- Canonical URL must appear in the hreflang set -- if not, all hreflang is ignored
- Canonical overrides hreflang when they conflict
- Protocol/domain must be consistent across canonical, hreflang, and sitemap (`https` + same domain variant)
- Paginated locale pages: self-referencing canonical per page (never canonical page 2+ to page 1)

**Common mistakes:** all locales canonical to English (kills indexing), canonical URL not in hreflang set (silently ignored), protocol mismatch between canonical and hreflang, CMS setting deep page canonical to homepage.

### International Sitemaps

**Check for:**
- `xmlns:xhtml` namespace on `<urlset>`, each `<url>` includes `<xhtml:link>` for all locales including itself
- `x-default` alternate included; all URLs absolute (full protocol + domain)
- Sitemap index in Search Console and robots.txt; split by content type, not by locale

**Next.js caveat:** `alternates.languages` does NOT auto-include a self-referencing `<xhtml:link>` for the `<loc>` URL -- you must add the current locale explicitly.

### Locale URL Structure

**Recommended:** Subdirectories (`/en/`, `/ar/`). **Acceptable:** Subdomains or ccTLDs. **Not recommended:** URL parameters (`?lang=en`).

**Check for:**
- Consistent locale prefix strategy; all locales prefixed (hiding locale from URLs prevents Google from distinguishing versions)
- Root URL handled as `x-default` with redirect, or serves default locale content
- No IP/Accept-Language content negotiation (Googlebot: US IPs, no Accept-Language header)
- Trailing slash + case consistency across locale paths, canonicals, hreflang, and sitemaps
- 301 redirects from non-canonical format to canonical

**Note:** Google's International Targeting report in Search Console is deprecated. Geotargeting relies on hreflang