| name | seo-hreflang |
| description | Hreflang and international SEO audit for multi-language and multi-region sites. Validates language-region codes, return tags, x-default, canonical alignment, and conflict detection across the per-URL HTML, the SE Ranking audit, and the XML sitemap. Use when the user asks "hreflang", "international SEO", "i18n", "language targeting", "x-default", "regional sites", or "multi-language SEO". |
Example output: examples/seo-hreflang-airbnb-com-20260514/HREFLANG-REPORT.md
Hreflang Audit
Adapted from AgriciDaniel/claude-seo's seo-hreflang skill (MIT). Concept and validation rules originate there; this implementation is rebuilt against our backend (SE Ranking MCP + Firecrawl + WebFetch + Google APIs via seo-google).
Validate hreflang implementations on a multi-language or multi-region site. Surface SE Ranking audit-level hreflang issues, parse a sample of pages for the actual <link rel="alternate" hreflang="…"> tags they emit, cross-check the sitemap, and produce one of three verdicts — PASS, NEEDS-FIX, or BROKEN — with a top-fixes table anchored in objective signals.
Prerequisites
- SE Ranking MCP server connected.
- Claude's
WebFetch tool available (fallback when Firecrawl is unavailable).
- User provides: a target domain (e.g.
example.com). Optional: explicit list of representative pages to inventory; explicit sitemap URL if not at /sitemap.xml.
- Predecessor (recommended):
seo-technical-audit or seo-sitemap already run on this domain. Without an existing audit, the skill creates one (which costs significantly more credits).
Process
-
Validate target & preflight. See skills/seo-firecrawl/references/preflight.md for the canonical 3-stage preflight (credit balance, Firecrawl availability, Google APIs). Skill-specific notes:
- Normalise domain (strip protocol, trailing slash) before continuing.
- Estimated SE Ranking cost for this skill: ~5–10 SE Ranking credits for re-using an existing audit (up to ~3 Firecrawl credits for the per-URL inventory).
- Firecrawl: optional with WebFetch fallback, ~6 Firecrawl credits if available (hard cap). When available, step 4 (per-URL hreflang inventory) runs on homepage + 5 representative pages with
formats: ["rawHtml"]. Without Firecrawl, step 4 falls back to WebFetch — coverage is degraded because WebFetch returns markdown only and silently strips <link rel="alternate"> tags from <head>. Pass --no-firecrawl to force WebFetch even when Firecrawl is available.
- Google APIs: tier 1 (GSC) unlocks step 6 (GSC verification of hreflang-targeted alternates). See
skills/seo-google/references/cross-skill-integration.md for the full enrichment contract.
-
Find or refresh the audit DATA_listAudits → DATA_getAuditStatus
- List audits for the domain. If a recent audit exists (<30 days), use it.
- If older than 30 days, run
DATA_recheckAudit and wait for done.
- If none exists, ask the user before creating one with
DATA_createStandardAudit — it consumes credits.
-
Pull SE Ranking's hreflang findings DATA_getAuditReport + DATA_getAuditPagesByIssue
- SE Ranking's audit catches hreflang errors directly — surface them first as ground truth.
- From
DATA_getAuditReport, extract every issue with code or category matching hreflang (typical codes: hreflang_no_return_tag, hreflang_invalid_lang_code, hreflang_conflict, hreflang_missing_x_default, hreflang_canonical_mismatch, hreflang_no_self_reference).
- For each significant hreflang issue (count ≥ 1), call
DATA_getAuditPagesByIssue to enumerate the affected URLs.
- Persist to
01-audit-hreflang-issues.md and feed into hreflang-issues.csv.
-
Per-URL hreflang tag inventory mcp__firecrawl-mcp__firecrawl_scrape (preferred) / WebFetch (fallback)
- Sample selection: homepage + up to 5 representative pages from
DATA_getDomainPages (sort by traffic descending; bias toward pages on different language paths if the URL structure exposes them — /en/, /fr/, /de/, etc.).
- Firecrawl path (1 credit per URL, ~6 total): call
firecrawl_scrape(url=..., formats=["rawHtml"]). Pin rawHtml — the default html post-processing strips <link rel="alternate"> on many sites. Parse every <link rel="alternate" hreflang="…" href="…"> from the <head>. Capture: source URL, hreflang attribute, href, and whether it's self-referencing.
- WebFetch fallback (no Firecrawl): try fetching each URL and extracting hreflang from the markdown response. WebFetch frequently returns markdown that has stripped
<head> link tags, so this path will under-report. Note in HREFLANG-REPORT.md: Per-URL inventory: degraded coverage — Firecrawl not installed; some hreflang tags may be missed.
- Apply validation rules (see references/validation-rules.md for the full list):
- Self-referencing tag: the page's own URL must appear in its own hreflang set.
- Return tags: every alternate link must reciprocate. If page A lists B as
fr, page B must list A as en (or whichever).
- x-default: at least one alternate per set must use
hreflang="x-default".
- Language-region code validation: every value must be a valid ISO 639-1 language (optionally followed by
- and an ISO 3166-1 Alpha-2 region). Common errors caught: eng (use en), jp (use ja), en-uk (use en-GB), es-LA (no such ISO region).
- Conflict detection: the same hreflang value (e.g.
de-DE) appearing on multiple distinct URLs is a conflict — Google ignores conflicting sets.
- Canonical alignment: if the page has
<link rel="canonical">, it must match the page's own URL (or its self-referencing hreflang URL). Hreflang on a non-canonical page is silently ignored by Google.
- Protocol consistency: all URLs in a set must share the same scheme (HTTPS preferred).
- Persist to
02-per-url-hreflang.md and append findings to hreflang-issues.csv.
-
Sitemap-level hreflang (defer to seo-sitemap where appropriate)
- If the user's domain uses sitemap-based hreflang (
<xhtml:link rel="alternate" …> inside the sitemap), this skill checks structure and consistency only. Full sitemap analysis (orphans, missing pages, broken entries) is seo-sitemap's job — recommend it explicitly if a sitemap-vs-audit diff is in scope.
- Fetch the sitemap. Try
https://{domain}/sitemap.xml; if 404, fetch /robots.txt and find Sitemap: directives. For sitemap-of-sitemaps, recursively fetch each child.
- Validate hreflang within the sitemap:
- Does the sitemap use the
xmlns:xhtml="http://www.w3.org/1999/xhtml" namespace? Required for hreflang in sitemaps.
- Does each
<url> entry that has hreflang alternates include itself in the alternate set (self-reference)?
- Does every alternate listed in one
<url> entry reciprocate as its own <url> entry with the same alternate set (return tags)?
- Are language-region codes valid (apply same rules as step 4)?
- Cross-check against per-URL inventory (step 4): if a sample URL's HTML lists 4 hreflang alternates but the sitemap entry for that URL lists 6, that mismatch is a conflict — Google may pick either, and inconsistency degrades the signal.
- Persist to
03-sitemap-hreflang.md and append findings to hreflang-issues.csv.
-
GSC verification of hreflang-targeted alternates (only if google-api.json is present, tier ≥ 1)
- For each unique domain that appears as an
href target in the hreflang sets (e.g. example.com, example.de, example.fr), confirm GSC verification:
python3 scripts/gsc_query.py --property "{property}" --json (a status-only check; just confirm the property responds without PROPERTY_NOT_VERIFIED).
- Why this matters: Google explicitly recommends verifying every domain that participates in a cross-domain hreflang setup. If
example.de is listed as an alternate but isn't verified in this account, the hreflang signal is weakened and you can't see how Google interprets it.
- Surface in
HREFLANG-REPORT.md as a section "## GSC verification of hreflang targets" with one row per target domain: verified / not verified / not configured.
- If property not verified for a target domain: list it as a fix at Medium severity ("Verify {domain} in Google Search Console — required for cross-domain hreflang trust").
- See
skills/seo-google/references/cross-skill-integration.md § "Trigger pattern" for the failure-mode contract.
-
Synthesise verdict
- Apply the verdict heuristic (see Tips) to produce PASS, NEEDS-FIX, or BROKEN.
- Sort
hreflang-issues.csv by severity descending, then count descending.
- Write
HREFLANG-REPORT.md with the top-fixes table (top 10) and the verdict.
Output format
Create a folder seo-hreflang-{target-slug}-{YYYYMMDD}/ with:
seo-hreflang-{target-slug}-{YYYYMMDD}/
├── 01-audit-hreflang-issues.md (SE Ranking audit findings filtered to hreflang)
├── 02-per-url-hreflang.md (per-URL <link rel="alternate"> inventory + validation findings)
├── 03-sitemap-hreflang.md (sitemap-level hreflang validation; defer details to seo-sitemap)
├── evidence/
│ ├── homepage-rawhtml.html (raw HTML from Firecrawl, for the homepage sample)
│ ├── sample-{n}-rawhtml.html (raw HTML for each sampled URL)
│ └── sitemap.xml (raw fetched sitemap)
├── hreflang-issues.csv (load-bearing: URL, issue code, severity, fix)
└── HREFLANG-REPORT.md (PRIMARY: verdict + top fixes table)
HREFLANG-REPORT.md follows this shape:
# Hreflang Audit: {domain}
> Audit date {YYYY-MM-DD} · Sample size: {n} URLs · Languages detected: {comma-separated list}
## Verdict: {PASS | NEEDS-FIX | BROKEN}
Reasoning: {1–2 sentences anchored in concrete numbers from the data}.
## Summary
| Source | Findings | Severity breakdown |
|---|---|---|
| SE Ranking audit | {n} | Critical: {n} · High: {n} · Medium: {n} · Low: {n} |
| Per-URL HTML inventory | {n} | … |
| Sitemap | {n} | … |
## Top fixes (impact-ranked)
| # | URL | Issue | Severity | Fix |
|---|---|---|---|---|
| 1 | {URL} | {issue code} | {severity} | {one-line fix} |
| 2 | … | … | … | … |
| ... up to 10 |
## Languages detected
| Language | URL count | Self-ref OK | Return tags OK | x-default OK |
|---|---|---|---|---|
| en-US | {n} | ✓ / ✗ {count} | ✓ / ✗ | ✓ / ✗ |
| de-DE | {n} | … | … | … |
| ... |
## Per-URL inventory ({n} URLs sampled)
| URL | Alternates | Self-ref | x-default | Notable issues |
|---|---|---|---|---|
| {URL} | {n} | ✓/✗ | ✓/✗ | {short text} |
| ... |
## Sitemap-level hreflang
- xhtml namespace declared: {✓/✗}
- URLs with hreflang alternates: {n}
- Self-reference within sitemap: {✓ all / ✗ {count} missing}
- Return tags within sitemap: {✓ all / ✗ {count} missing}
- Per-URL HTML vs sitemap consistency: {✓ all match / ✗ {count} mismatched}
- Full sitemap-vs-audit analysis: see `seo-sitemap` (orphans, broken entries, lastmod).
## GSC verification of hreflang targets
| Domain | Verified | Notes |
|---|---|---|
| {domain1} | ✓ / ✗ | {note if unverified} |
| ... |
(Or: `GSC verification: not configured (run bash extensions/google/install.sh)`.)
## Coverage notes
- Per-URL inventory tool: {Firecrawl rawHtml | WebFetch fallback (degraded — some hreflang tags may be missed)}.
- Pages sampled: homepage + {n} representative pages (selection: top traffic from `DATA_getDomainPages`).
## Apply
- Walk `hreflang-issues.csv` row-by-row; each row is one specific change (URL + issue + fix).
- After applying changes, re-run `seo-technical-audit` to refresh SE Ranking's findings, then re-run this skill to verify.
hreflang-issues.csv columns: url,issue_code,severity,fix,source where source is one of audit | html | sitemap | gsc.
Tips
- Respect SE Ranking Data API rate limit: 10 req/sec.
- Reuse existing audits when possible — creating a new audit is by far the most expensive operation in this skill.
- Verdict heuristic:
- PASS: zero Critical findings; ≤ 2 High findings; sample URLs all have self-reference, x-default, and reciprocal return tags; all language-region codes valid; canonical aligns with self-ref hreflang.
- NEEDS-FIX: any High finding; or > 5 Medium findings; or any one of (missing x-default, missing return tags on > 25% of sampled pages, language-region code error, sitemap-vs-HTML mismatch).
- BROKEN: any Critical finding; or hreflang attempted but no self-reference on the homepage; or canonical pointing elsewhere on a page that nonetheless emits hreflang (entire set is ignored by Google); or > 50% of sampled URLs missing return tags.
- Anchor every claim in
HREFLANG-REPORT.md to a row in hreflang-issues.csv. If a stakeholder questions the verdict, walk them through the CSV.
- For sites with > 50 language variants per page, the per-URL HTML implementation bloats the
<head> — recommend the sitemap-based implementation instead. Don't generate code; the deliverable is diagnostic, not code-gen.
- The skill does not assess cultural adaptation, content parity, or locale formatting. Those are translation/QA concerns; they're orthogonal to whether hreflang itself is technically correct. If the user wants those, point them at the translation team — this skill answers "is the technical hreflang signal working?", not "is the localised content good?".
- For cross-domain hreflang (e.g.
example.com ↔ example.de), step 6's GSC check is the highest-value enrichment — verifying both domains is Google's explicit recommendation.
- Common false-positive guard: if a sampled page legitimately has no internationalization (e.g. a single-region site), zero hreflang tags is correct, not an issue. The skill detects this by checking whether any sampled page emits hreflang; if none do, the verdict is PASS with note "No hreflang implementation detected — single-language site."
- Pair with
seo-sitemap for the sitemap-vs-audit diff; pair with seo-technical-audit for full technical health. This skill is narrow: hreflang correctness only.
- See
references/validation-rules.md for the full per-issue rule table (severity, detection logic, suggested fix).
