technical-seo-checker

name	technical-seo-checker
description	Performs technical SEO audits covering site speed, crawlability, indexability, mobile-friendliness, security, and structured data. Identifies technical issues preventing optimal search performance.

Technical SEO Checker

This skill performs comprehensive technical SEO audits to identify issues that may prevent search engines from properly crawling, indexing, and ranking your site.

When to Use This Skill

• 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

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

How to Use

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]

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] |
   
   
   
   | 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] |
   
   : [X]/10
   

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

User: "Check the technical SEO of example.com"

Output: [Comprehensive technical audit following the structure above]

Technical SEO Checklist

### Crawlability
- [ ] robots.txt is valid and not blocking important content
- [ ] XML sitemap exists and is submitted to ~~search console
- [ ] No crawl errors in ~~search console
- [ ] No redirect chains or loops

### Indexability  
- [ ] Important pages are indexable
- [ ] Canonical tags are correct
- [ ] No duplicate content issues
- [ ] Pagination is handled correctly

### Performance
- [ ] Core Web Vitals pass
- [ ] Page speed under 3 seconds
- [ ] Images are optimized
- [ ] JS/CSS are minified

### Mobile
- [ ] Mobile-friendly test passes
- [ ] Viewport is configured
- [ ] Touch elements are properly sized

### Security
- [ ] HTTPS is enforced
- [ ] SSL certificate is valid
- [ ] No mixed content
- [ ] Security headers present

### Structure
- [ ] URLs are clean and descriptive
- [ ] Site architecture is logical
- [ ] Internal linking is strong

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

Reference Materials

• robots.txt Reference - Syntax guide, templates, common configurations
• HTTP Status Codes - SEO impact of each status code, redirect best practices

Related Skills

• on-page-seo-auditor - On-page SEO audit
• schema-markup-generator - Fix schema issues
• performance-reporter - Monitor improvements
• internal-linking-optimizer - Fix link issues