Technical Seo Checker

When This Must Trigger

Use this when the conversation involves any of these situations — even if the user does not use SEO terminology:

Use this whenever the task needs a diagnosis or repair plan that should feed directly into remediation work, not just a one-time opinion.

• Launching a new website
• Diagnosing ranking drops
• Pre-migration SEO audits
• Regular technical health checks
• Identifying crawl and index issues
• Improving site performance
• Fixing Core Web Vitals issues

Technical SEO Coverage

This skill audits the infrastructure layer that determines whether search engines can crawl, index, and rank your pages: robots.txt and XML sitemap correctness, canonical tags, redirect chains, and crawl budget management.

Core Web Vitals (LCP, CLS, INP) are measured as direct ranking factors alongside page speed and mobile-first indexing compliance. Structured data markup is validated for rich results, and hreflang is checked for international sites. All findings are ranked by SEO impact so teams can prioritize fixes that unblock organic traffic growth immediately.

What This Skill Does

1. Crawlability Audit: Checks robots.txt, sitemaps, crawl issues
2. Indexability Review: Analyzes index status and blockers
3. Site Speed Analysis: Evaluates Core Web Vitals and performance
4. Mobile-Friendliness: Checks mobile optimization
5. Security Check: Reviews HTTPS and security headers
6. Structured Data Audit: Validates schema markup
7. URL Structure Analysis: Reviews URL patterns and redirects
8. International SEO: Checks hreflang and localization

Quick Start

Start with one of these prompts. Finish with a short handoff summary using the repository format in Skill Contract.

Full Technical Audit

Perform a technical SEO audit for [URL/domain]

Specific Issue Check

Check Core Web Vitals for [URL]

Audit crawlability and indexability for [domain]

Pre-Migration Audit

Technical SEO checklist for migrating [old domain] to [new domain]

Skill Contract

Expected output: a scored diagnosis, prioritized repair plan, and a short handoff summary ready for memory/audits/.

• Reads: the current page or site state, symptoms, prior audits, and current priorities from CLAUDE.md and the shared State Model when available.
• Writes: a user-facing audit or optimization plan plus a reusable summary that can be stored under memory/audits/.
• Promotes: blocking defects, repeated weaknesses, and fix priorities to memory/open-loops.md and memory/decisions.md.
• Next handoff: use the Next Best Skill below when the repair path is clear.

Data Sources

See CONNECTORS.md for tool category placeholders.

With ~~web crawler + ~~page speed tool + ~~CDN connected: Claude can automatically crawl the entire site structure via ~~web crawler, pull Core Web Vitals and performance metrics from ~~page speed tool, analyze caching headers from ~~CDN, and fetch mobile-friendliness data. This enables comprehensive automated technical audits.

With manual data only: Ask the user to provide:

1. Site URL(s) to audit
2. PageSpeed Insights screenshots or reports
3. robots.txt file content
4. sitemap.xml URL or file

Proceed with the full audit using provided data. Note in the output which findings are from automated crawl vs. manual review.

Instructions

When a user requests a technical SEO audit:

1. Audit Crawlability

   ## Crawlability Analysis
   
   ### Robots.txt Review
   
   **URL**: [domain]/robots.txt
   **Status**: [Found/Not Found/Error]
   
   **Current Content**:
   

   [robots.txt content]

   
   | Check | Status | Notes |
   |-------|--------|-------|
   | File exists | ✅/❌ | [notes] |
   | Valid syntax | ✅/⚠️/❌ | [errors found] |
   | Sitemap declared | ✅/❌ | [sitemap URL] |
   | Important pages blocked | ✅/⚠️/❌ | [blocked paths] |
   | Assets blocked | ✅/⚠️/❌ | [CSS/JS blocked?] |
   | Correct user-agents | ✅/⚠️/❌ | [notes] |
   
   **Issues Found**:
   - [Issue 1]
   - [Issue 2]
   
   **Recommended robots.txt**:
   

   User-agent: * Allow: / Disallow: /admin/ Disallow: /private/

   Sitemap: https://example.com/sitemap.xml

   
   ---
   
   ### XML Sitemap Review
   
   **Sitemap URL**: [URL]
   **Status**: [Found/Not Found/Error]
   
   | Check | Status | Notes |
   |-------|--------|-------|
   | Sitemap exists | ✅/❌ | [notes] |
   | Valid XML format | ✅/⚠️/❌ | [errors] |
   | In robots.txt | ✅/❌ | [notes] |
   | Submitted to ~~search console | ✅/⚠️/❌ | [notes] |
   | URLs count | [X] | [appropriate?] |
   | Only indexable URLs | ✅/⚠️/❌ | [notes] |
   | Includes priority | ✅/⚠️ | [notes] |
   | Includes lastmod | ✅/⚠️ | [accurate?] |
   
   **Issues Found**:
   - [Issue 1]
   
   ---
   
   ### Crawl Budget Analysis
   
   | Factor | Status | Impact |
   |--------|--------|--------|
   | Crawl errors | [X] errors | [Low/Med/High] |
   | Duplicate content | [X] pages | [Low/Med/High] |
   | Thin content | [X] pages | [Low/Med/High] |
   | Redirect chains | [X] found | [Low/Med/High] |
   | Orphan pages | [X] found | [Low/Med/High] |
   
   **Crawlability Score**: [X]/10
   

2. Audit Indexability

   ## Indexability Analysis
   
   ### Index Status Overview
   
   | Metric | Count | Notes |
   |--------|-------|-------|
   | Pages in sitemap | [X] | |
   | Pages indexed | [X] | [source: site: search] |
   | Index coverage ratio | [X]% | [good if >90%] |
   
   ### Index Blockers Check
   
   | Blocker Type | Found | Pages Affected |
   |--------------|-------|----------------|
   | noindex meta tag | [X] | [list or "none"] |
   | noindex X-Robots | [X] | [list or "none"] |
   | Robots.txt blocked | [X] | [list or "none"] |
   | Canonical to other | [X] | [list or "none"] |
   | 4xx/5xx errors | [X] | [list or "none"] |
   | Redirect loops | [X] | [list or "none"] |
   
   ### Canonical Tags Audit
   
   | Check | Status | Notes |
   |-------|--------|-------|
   | Canonicals present | ✅/⚠️/❌ | [X]% of pages |
   | Self-referencing | ✅/⚠️/❌ | [notes] |
   | Consistent (HTTP/HTTPS) | ✅/⚠️/❌ | [notes] |
   | Consistent (www/non-www) | ✅/⚠️/❌ | [notes] |
   | No conflicting signals | ✅/⚠️/❌ | [notes] |
   
   ### Duplicate Content Issues
   
   | Issue Type | Count | Examples |
   |------------|-------|----------|
   | Exact duplicates | [X] | [URLs] |
   | Near duplicates | [X] | [URLs] |
   | Parameter duplicates | [X] | [URLs] |
   | WWW/non-WWW | [X] | [notes] |
   | HTTP/HTTPS | [X] | [notes] |
   
   **Indexability Score**: [X]/10
   

3. Audit Site Speed & Core Web Vitals — CWV metrics (LCP/FID/CLS/INP), additional performance metrics (TTFB/FCP/Speed Index/TBT), resource loading breakdown, optimization recommendations

   Reference: See references/technical-audit-templates.md for the performance analysis template (Step 3).

4. Audit Mobile-Friendliness — Mobile-friendly test, responsive design check, mobile-first indexing verification

   Reference: See references/technical-audit-templates.md for the mobile optimization template (Step 4).

5. Audit Security & HTTPS — SSL certificate, HTTPS enforcement, mixed content, HSTS, security headers (CSP, X-Frame-Options, etc.)

   Reference: See references/technical-audit-templates.md for the security analysis template (Step 5).

6. Audit URL Structure — URL patterns, issues (dynamic params, session IDs, uppercase), redirect analysis (chains, loops, 302s)

   Reference: See references/technical-audit-templates.md for the URL structure template (Step 6).

7. Audit Structured Data — Schema markup validation, missing schema opportunities. CORE-EEAT alignment: maps to O05.

   Reference: See references/technical-audit-templates.md for the structured data template (Step 7).

8. Audit International SEO (if applicable) — Hreflang implementation, language/region targeting

   Reference: See references/technical-audit-templates.md for the international SEO template (Step 8).

9. Generate Technical Audit Summary — Overall health score with visual breakdown, critical/high/medium issues, quick wins, implementation roadmap (weeks 1-4+), monitoring recommendations

   Reference: See references/technical-audit-templates.md for the audit summary template (Step 9).

Validation Checkpoints

Input Validation

• Site URL or domain clearly specified
• Access to technical data (robots.txt, sitemap, or crawl results)
• Performance metrics available (via ~~page speed tool or screenshots)

Output Validation

• Every recommendation cites specific data points (not generic advice)
• All issues include affected URLs or page counts
• Performance metrics include actual numbers with units (seconds, KB, etc.)
• Source of each data point clearly stated (~~web crawler data, ~~page speed tool, user-provided, or estimated)

Example

Reference: See references/technical-audit-example.md for a full worked example (cloudhosting.com technical audit) and the comprehensive technical SEO checklist.

Tips for Success

1. Prioritize by impact - Fix critical issues first
2. Monitor continuously - Use ~~search console alerts
3. Test changes - Verify fixes work before deploying widely
4. Document everything - Track changes for troubleshooting
5. Regular audits - Schedule quarterly technical reviews

Technical reference: For issue severity framework, prioritization matrix, and Core Web Vitals optimization quick reference, see references/http-status-codes.md.

Save Results

After delivering audit or optimization findings to the user, ask:

"Save these results for future sessions?"

If yes, write a dated summary to memory/audits/technical-seo-checker/YYYY-MM-DD-<topic>.md containing:

• One-line verdict or headline finding
• Top 3-5 actionable items
• Open loops or blockers
• Source data references

If any veto-level issue was found (CORE-EEAT T04, C01, R10 or CITE T03, T05, T09), also append a one-liner to memory/hot-cache.md without asking.

Reference Materials

• robots.txt Reference — Syntax guide, templates, common configurations
• HTTP Status Codes — SEO impact of each status code, redirect best practices
• Technical Audit Templates — Detailed output templates for steps 3-9 (CWV, mobile, security, URL structure, structured data, international, audit summary)
• Technical Audit Example & Checklist — Full worked example and comprehensive technical SEO checklist

Next Best Skill

• Primary: on-page-seo-auditor — continue from infrastructure issues into page-level remediation.

Related Skills in This Suite

Install the full suite: See README for one-command install of all 20 skills.