Technical SEO Checklist

When to Use This Skill

Use this skill when you need to:

• Conduct a technical SEO audit of a website
• Identify crawlability, indexation, and performance issues
• Create a prioritized checklist of technical fixes
• Assess Core Web Vitals and structured data implementation

DO NOT use this skill for content strategy, keyword research, or link building. This is for the technical foundation that enables content to rank.

Core Principle

TECHNICAL SEO REMOVES THE BARRIERS BETWEEN YOUR CONTENT AND SEARCH ENGINES — IF GOOGLE CANNOT CRAWL, INDEX, AND RENDER YOUR PAGES CORRECTLY, NO AMOUNT OF GREAT CONTENT WILL RANK.

Phase 1: Brief

Required Inputs

GATE: Confirm before building the audit checklist.

Phase 2: Technical Audit Checklist

Crawlability

## Crawlability Checks

- [ ] Robots.txt exists and is accessible at /robots.txt
- [ ] Robots.txt is not blocking important pages or resources
- [ ] XML sitemap exists at /sitemap.xml
- [ ] Sitemap is submitted to Google Search Console
- [ ] Sitemap contains only 200-status URLs (no 404s, no redirects)
- [ ] Sitemap is updated automatically when content is published
- [ ] No orphan pages (pages with zero internal links)
- [ ] Crawl depth: all important pages within 3 clicks of homepage
- [ ] No redirect chains (A→B→C; should be A→C)
- [ ] No redirect loops
- [ ] Server responds within 200ms for the majority of pages

Indexation

## Indexation Checks

- [ ] Site:domain.com shows expected number of indexed pages
- [ ] No important pages blocked by noindex tags
- [ ] No important pages blocked by robots.txt
- [ ] Canonical tags present and pointing to correct URLs
- [ ] No duplicate content (multiple URLs for same content)
- [ ] Pagination handled correctly (rel=prev/next or load-more)
- [ ] URL parameters not creating duplicate pages
- [ ] Hreflang tags correct (if multi-language)
- [ ] Google Search Console: Coverage report shows no unexpected errors

Core Web Vitals

## Performance Checks

**Largest Contentful Paint (LCP):** Target < 2.5 seconds
- [ ] Hero images optimized (compressed, proper dimensions)
- [ ] Server response time under 200ms
- [ ] No render-blocking CSS/JS above the fold

**Interaction to Next Paint (INP):** Target < 200ms
- [ ] JavaScript execution optimized
- [ ] No long tasks blocking the main thread
- [ ] Event handlers are efficient

**Cumulative Layout Shift (CLS):** Target < 0.1
- [ ] All images have width/height attributes
- [ ] No dynamically injected content above the fold
- [ ] Web fonts loaded with font-display: swap
- [ ] Ad slots have reserved dimensions

On-Page Technical Elements

## On-Page Checks

- [ ] HTTPS enabled site-wide (no mixed content)
- [ ] One H1 tag per page
- [ ] Title tags unique and under 60 characters
- [ ] Meta descriptions unique and 150-160 characters
- [ ] Image alt text present on all meaningful images
- [ ] Images compressed and served in modern formats (WebP)
- [ ] Lazy loading implemented for below-fold images
- [ ] Mobile-responsive design (passes Google Mobile-Friendly Test)
- [ ] No broken internal links (404 errors)
- [ ] No broken external links

Structured Data

## Structured Data Checks

- [ ] Organization or LocalBusiness schema on homepage
- [ ] Article schema on blog posts
- [ ] BreadcrumbList schema on all inner pages
- [ ] FAQ schema where applicable
- [ ] Product schema on product pages
- [ ] No schema validation errors (test with Rich Results Test)

GATE: Present the checklist with current findings for review.

Phase 3: Prioritized Fix List

Priority Matrix

Categorize each issue found:

## Fix Priority

**Critical (fix immediately):**
- Issues that block crawling or indexation
- Noindex on important pages
- Sitewide 500 errors
- HTTPS not enabled

**High (fix this week):**
- Core Web Vitals failures
- Broken internal links (404s)
- Missing canonical tags causing duplication
- Redirect chains

**Medium (fix this month):**
- Missing structured data
- Image optimization
- Missing alt text
- Sitemap issues

**Low (fix when possible):**
- External broken links
- Minor CLS issues
- Metadata length optimization
- Font loading improvements

Issue-by-Issue Fix Guide

For each issue found, provide:

1. What the issue is
2. Why it matters for SEO
3. How to fix it (specific steps)
4. Tools to verify the fix

Phase 4: Polish

1. Monitoring Setup

• Google Search Console: check weekly for new crawl errors
• Core Web Vitals: monitor via PageSpeed Insights monthly
• Uptime monitoring: set up alerts for downtime
• Broken link checker: run monthly

2. Quarterly Audit Schedule

• Full technical audit every quarter
• Focus areas rotate: Q1 crawlability, Q2 performance, Q3 indexation, Q4 structured data
• Document changes and improvements each quarter

3. Tool Recommendations

• Free: Google Search Console, PageSpeed Insights, Rich Results Test, Mobile-Friendly Test
• Budget: Screaming Frog (free up to 500 URLs), Lighthouse
• Premium: Ahrefs Site Audit, SEMrush Site Audit, Sitebulb

Anti-Patterns

• Fixing everything at once — prioritize critical issues first. Trying to fix 50 things simultaneously leads to nothing being done well.
• Ignoring Core Web Vitals — performance is a ranking factor. Slow sites lose rankings and visitors.
• Blocking CSS/JS in robots.txt — search engines need to render your pages. Blocking resources prevents proper indexing.
• No monitoring after fixes — technical issues recur. Set up monitoring to catch problems early.
• Over-optimizing at the expense of user experience — technical SEO serves users first. Don't break the site to fix a minor SEO issue.

Recovery

• Site not indexed at all: Check robots.txt for Disallow: /, check for sitewide noindex, verify DNS and hosting are correct.
• Massive crawl errors after migration: Implement redirect map immediately. Check the seo-migration-plan skill for recovery steps.
• Core Web Vitals failing across the site: Start with the homepage and top 10 traffic pages. Optimize images and eliminate render-blocking resources first.
• Non-technical user: Focus on the top 5 highest-impact issues and provide specific step-by-step instructions for their platform (WordPress plugin recommendations, etc.).