Claude-seo seo-technical

install
source · Clone the upstream repo
git clone https://github.com/AgriciDaniel/claude-seo
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/AgriciDaniel/claude-seo "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/seo-technical" ~/.claude/skills/agricidaniel-claude-seo-seo-technical && rm -rf "$T"
manifest: skills/seo-technical/SKILL.md
source content

Technical SEO Audit

Categories

1. Crawlability

  • robots.txt: exists, valid, not blocking important resources
  • XML sitemap: exists, referenced in robots.txt, valid format
  • Noindex tags: intentional vs accidental
  • Crawl depth: important pages within 3 clicks of homepage
  • JavaScript rendering: check if critical content requires JS execution
  • Crawl budget: for large sites (>10k pages), efficiency matters

AI Crawler Management

As of 2025-2026, AI companies actively crawl the web to train models and power AI search. Managing these crawlers via robots.txt is a critical technical SEO consideration.

Known AI crawlers:

CrawlerCompanyrobots.txt tokenPurpose
GPTBotOpenAI
GPTBot
Model training
ChatGPT-UserOpenAI
ChatGPT-User
Real-time browsing
ClaudeBotAnthropic
ClaudeBot
Model training
PerplexityBotPerplexity
PerplexityBot
Search index + training
BytespiderByteDance
Bytespider
Model training
Google-ExtendedGoogle
Google-Extended
Gemini training (NOT search)
CCBotCommon Crawl
CCBot
Open dataset

Key distinctions:

  • Blocking
    Google-Extended
    prevents Gemini training use but does NOT affect Google Search indexing or AI Overviews (those use
    Googlebot
    )
  • Blocking
    GPTBot
    prevents OpenAI training but does NOT prevent ChatGPT from citing your content via browsing (
    ChatGPT-User
    )
  • ~3-5% of websites now use AI-specific robots.txt rules

Example, selective AI crawler blocking:

# Allow search indexing, block AI training crawlers
User-agent: GPTBot
Disallow: /

User-agent: Google-Extended
Disallow: /

User-agent: Bytespider
Disallow: /

# Allow all other crawlers (including Googlebot for search)
User-agent: *
Allow: /

Recommendation: Consider your AI visibility strategy before blocking. Being cited by AI systems drives brand awareness and referral traffic. Cross-reference the

seo-geo
skill for full AI visibility optimization.

2. Indexability

  • Canonical tags: self-referencing, no conflicts with noindex
  • Duplicate content: near-duplicates, parameter URLs, www vs non-www
  • Thin content: pages below minimum word counts per type
  • Pagination: rel=next/prev or load-more pattern
  • Hreflang: correct for multi-language/multi-region sites
  • Index bloat: unnecessary pages consuming crawl budget

3. Security

  • HTTPS: enforced, valid SSL certificate, no mixed content
  • Security headers:
    • Content-Security-Policy (CSP)
    • Strict-Transport-Security (HSTS)
    • X-Frame-Options
    • X-Content-Type-Options
    • Referrer-Policy
  • HSTS preload: check preload list inclusion for high-security sites

4. URL Structure

  • Clean URLs: descriptive, hyphenated, no query parameters for content
  • Hierarchy: logical folder structure reflecting site architecture
  • Redirects: no chains (max 1 hop), 301 for permanent moves
  • URL length: flag >100 characters
  • Trailing slashes: consistent usage

5. Mobile Optimization

  • Responsive design: viewport meta tag, responsive CSS
  • Touch targets: minimum 48x48px with 8px spacing
  • Font size: minimum 16px base
  • No horizontal scroll
  • Mobile-first indexing: Google indexes mobile version. Mobile-first indexing is 100% complete as of July 5, 2024. Google now crawls and indexes ALL websites exclusively with the mobile Googlebot user-agent.

6. Core Web Vitals

  • LCP (Largest Contentful Paint): target <2.5s
  • INP (Interaction to Next Paint): target <200ms
    • INP replaced FID on March 12, 2024. FID was fully removed from all Chrome tools (CrUX API, PageSpeed Insights, Lighthouse) on September 9, 2024. Do NOT reference FID anywhere.
  • CLS (Cumulative Layout Shift): target <0.1
  • Evaluation uses 75th percentile of real user data
  • Use PageSpeed Insights API or CrUX data if MCP available

7. Structured Data

  • Detection: JSON-LD (preferred), Microdata, RDFa
  • Validation against Google's supported types
  • See seo-schema skill for full analysis

8. JavaScript Rendering

  • Check if content visible in initial HTML vs requires JS
  • Identify client-side rendered (CSR) vs server-side rendered (SSR)
  • Flag SPA frameworks (React, Vue, Angular) that may cause indexing issues
  • Verify dynamic rendering setup if applicable

JavaScript SEO: Canonical & Indexing Guidance (December 2025)

Google updated its JavaScript SEO documentation in December 2025 with critical clarifications:

  1. Canonical conflicts: If a canonical tag in raw HTML differs from one injected by JavaScript, Google may use EITHER one. Ensure canonical tags are identical between server-rendered HTML and JS-rendered output.
  2. noindex with JavaScript: If raw HTML contains
    <meta name="robots" content="noindex">
    but JavaScript removes it, Google MAY still honor the noindex from raw HTML. Serve correct robots directives in the initial HTML response.
  3. Non-200 status codes: Google does NOT render JavaScript on pages returning non-200 HTTP status codes. Any content or meta tags injected via JS on error pages will be invisible to Googlebot.
  4. Structured data in JavaScript: Product, Article, and other structured data injected via JS may face delayed processing. For time-sensitive structured data (especially e-commerce Product markup), include it in the initial server-rendered HTML.

Best practice: Serve critical SEO elements (canonical, meta robots, structured data, title, meta description) in the initial server-rendered HTML rather than relying on JavaScript injection.

9. IndexNow Protocol

  • Check if site supports IndexNow for Bing, Yandex, Naver
  • Supported by search engines other than Google
  • Recommend implementation for faster indexing on non-Google engines

Output

Technical Score: XX/100

Category Breakdown

CategoryStatusScore
Crawlabilitypass/warn/failXX/100
Indexabilitypass/warn/failXX/100
Securitypass/warn/failXX/100
URL Structurepass/warn/failXX/100
Mobilepass/warn/failXX/100
Core Web Vitalspass/warn/failXX/100
Structured Datapass/warn/failXX/100
JS Renderingpass/warn/failXX/100
IndexNowpass/warn/failXX/100

Critical Issues (fix immediately)

High Priority (fix within 1 week)

Medium Priority (fix within 1 month)

Low Priority (backlog)

DataForSEO Integration (Optional)

If DataForSEO MCP tools are available, use

on_page_instant_pages
for real page analysis (status codes, page timing, broken links, on-page checks),
on_page_lighthouse
for Lighthouse audits (performance, accessibility, SEO scores), and
domain_analytics_technologies_domain_technologies
for technology stack detection.

Google API Integration (Optional)

If Google API credentials are configured, use

python scripts/pagespeed_check.py <url> --json
for real PSI + CrUX field data (replaces lab-only CWV estimates),
python scripts/crux_history.py <url> --json
for 25-week CWV trends, and
python scripts/gsc_inspect.py <url> --json
for real indexation status per URL.

Error Handling

ScenarioAction
URL unreachableReport connection error with status code. Suggest verifying URL, checking DNS resolution, and confirming the site is publicly accessible.
robots.txt not foundNote that no robots.txt was detected at the root domain. Recommend creating one with appropriate directives. Continue audit on remaining categories.
HTTPS not configuredFlag as a critical issue. Report whether HTTP is served without redirect, mixed content exists, or SSL certificate is missing/expired.
Core Web Vitals data unavailableNote that CrUX data is not available (common for low-traffic sites). Suggest using Lighthouse lab data as a proxy and recommend increasing traffic before re-testing.