Technical SEO Checker
SEO & GEO Skills Library · 20 skills for SEO + GEO · Install all: npx skills add aaron-he-zhu/seo-geo-claude-skills
Research · keyword-research · competitor-analysis · serp-analysis · content-gap-analysis
Build · seo-content-writer · geo-content-optimizer · meta-tags-optimizer · schema-markup-generator
Optimize · on-page-seo-auditor · technical-seo-checker · internal-linking-optimizer · content-refresher
Monitor · rank-tracker · backlink-analyzer · performance-reporter · alert-manager
Cross-cutting · content-quality-auditor · domain-authority-auditor · entity-optimizer · memory-management
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
- Crawlability Audit: Checks robots.txt, sitemaps, crawl issues
- Indexability Review: Analyzes index status and blockers
- Site Speed Analysis: Evaluates Core Web Vitals and performance
- Mobile-Friendliness: Checks mobile optimization
- Security Check: Reviews HTTPS and security headers
- Structured Data Audit: Validates schema markup
- URL Structure Analysis: Reviews URL patterns and redirects
- 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:
- Site URL(s) to audit
- PageSpeed Insights screenshots or reports
- robots.txt file content
- 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:
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
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
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).
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).
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).
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).
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).
Audit International SEO (if applicable) — Hreflang implementation, language/region targeting
Reference: See references/technical-audit-templates.md for the international SEO template (Step 8).
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
Output Validation
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
- Prioritize by impact - Fix critical issues first
- Monitor continuously - Use ~~search console alerts
- Test changes - Verify fixes work before deploying widely
- Document everything - Track changes for troubleshooting
- 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.
Reference Materials
Related Skills
1---2name: technical-seo-checker-33description: This skill should be used when the user asks to "technical SEO audit", "check page speed", "Core Web Vitals", "LCP is slow", "CLS problem", "INP issues", "crawl errors", "indexing problems", "robots.txt check", "XML sitemap errors", "hreflang issues", "canonical tag problems", "HTTPS not working", "mobile SEO", "JavaScript rendering", or "site health check". Performs comprehensive technical SEO audits: Core Web Vitals (LCP/CLS/INP/TTFB), crawlability, indexability, mobile-friendliness, HTTPS/HSTS security, URL structure, redirect chains, robots.txt, XML sitemaps, hreflang, canonical tags, and structured data validation. Produces a scored technical health report (0–100) with critical/high/medium issue triage and a prioritized implementation roadmap. Works with Google PageSpeed Insights, Google Search Console, crawl tools, or manual audit. For content element issues, see on-page-seo-auditor. For link architecture, see internal-linking-optimizer.4license: Apache-2.05---6
7# Technical SEO Checker
8
9
10> **[SEO & GEO Skills Library](https://skills.sh/aaron-he-zhu/seo-geo-claude-skills)** · 20 skills for SEO + GEO · Install all: `npx skills add aaron-he-zhu/seo-geo-claude-skills`
11
12<details>
13<summary>Browse all 20 skills</summary>
14
15**Research** · [keyword-research](../../research/keyword-research/) · [competitor-analysis](../../research/competitor-analysis/) · [serp-analysis](../../research/serp-analysis/) · [content-gap-analysis](../../research/content-gap-analysis/)
16
17**Build** · [seo-content-writer](../../build/seo-content-writer/) · [geo-content-optimizer](../../build/geo-content-optimizer/) · [meta-tags-optimizer](../../build/meta-tags-optimizer/) · [schema-markup-generator](../../build/schema-markup-generator/)
18
19**Optimize** · [on-page-seo-auditor](../on-page-seo-auditor/) · **technical-seo-checker** · [internal-linking-optimizer](../internal-linking-optimizer/) · [content-refresher](../content-refresher/)
20
21**Monitor** · [rank-tracker](../../monitor/rank-tracker/) · [backlink-analyzer](../../monitor/backlink-analyzer/) · [performance-reporter](../../monitor/performance-reporter/) · [alert-manager](../../monitor/alert-manager/)
22
23**Cross-cutting** · [content-quality-auditor](../../cross-cutting/content-quality-auditor/) · [domain-authority-auditor](../../cross-cutting/domain-authority-auditor/) · [entity-optimizer](../../cross-cutting/entity-optimizer/) · [memory-management](../../cross-cutting/memory-management/)
24
25</details>
26
27This skill performs comprehensive technical SEO audits to identify issues that may prevent search engines from properly crawling, indexing, and ranking your site.
28
29## When to Use This Skill
30
31- Launching a new website
32- Diagnosing ranking drops
33- Pre-migration SEO audits
34- Regular technical health checks
35- Identifying crawl and index issues
36- Improving site performance
37- Fixing Core Web Vitals issues
38
39## What This Skill Does
40
411. **Crawlability Audit**: Checks robots.txt, sitemaps, crawl issues
422. **Indexability Review**: Analyzes index status and blockers
433. **Site Speed Analysis**: Evaluates Core Web Vitals and performance
444. **Mobile-Friendliness**: Checks mobile optimization
455. **Security Check**: Reviews HTTPS and security headers
466. **Structured Data Audit**: Validates schema markup
477. **URL Structure Analysis**: Reviews URL patterns and redirects
488. **International SEO**: Checks hreflang and localization
49
50## How to Use
51
52### Full Technical Audit
53
54```
55Perform a technical SEO audit for [URL/domain]
56```
57
58### Specific Issue Check
59
60```
61Check Core Web Vitals for [URL]
62```
63
64```
65Audit crawlability and indexability for [domain]
66```
67
68### Pre-Migration Audit
69
70```
71Technical SEO checklist for migrating [old domain] to [new domain]
72```
73
74## Data Sources
75
76> See [CONNECTORS.md](../../CONNECTORS.md) for tool category placeholders.
77
78**With ~~web crawler + ~~page speed tool + ~~CDN connected:**
79Claude 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.
80
81**With manual data only:**
82Ask the user to provide:
831. Site URL(s) to audit
842. PageSpeed Insights screenshots or reports
853. robots.txt file content
864. sitemap.xml URL or file
87
88Proceed with the full audit using provided data. Note in the output which findings are from automated crawl vs. manual review.
89
90## Instructions
91
92When a user requests a technical SEO audit:
93
941. **Audit Crawlability**
95
96 ```markdown
97 ## Crawlability Analysis
98
99 ### Robots.txt Review
100
101 **URL**: [domain]/robots.txt
102 **Status**: [Found/Not Found/Error]
103
104 **Current Content**:
105 ```
106 [robots.txt content]
107 ```
108
109 | Check | Status | Notes |
110 |-------|--------|-------|
111 | File exists | ✅/❌ | [notes] |
112 | Valid syntax | ✅/⚠️/❌ | [errors found] |
113 | Sitemap declared | ✅/❌ | [sitemap URL] |
114 | Important pages blocked | ✅/⚠️/❌ | [blocked paths] |
115 | Assets blocked | ✅/⚠️/❌ | [CSS/JS blocked?] |
116 | Correct user-agents | ✅/⚠️/❌ | [notes] |
117
118 **Issues Found**:
119 - [Issue 1]
120 - [Issue 2]
121
122 **Recommended robots.txt**:
123 ```
124 User-agent: *
125 Allow: /
126 Disallow: /admin/
127 Disallow: /private/
128
129 Sitemap: https://example.com/sitemap.xml
130 ```
131
132 ---
133
134 ### XML Sitemap Review
135
136 **Sitemap URL**: [URL]
137 **Status**: [Found/Not Found/Error]
138
139 | Check | Status | Notes |
140 |-------|--------|-------|
141 | Sitemap exists | ✅/❌ | [notes] |
142 | Valid XML format | ✅/⚠️/❌ | [errors] |
143 | In robots.txt | ✅/❌ | [notes] |
144 | Submitted to ~~search console | ✅/⚠️/❌ | [notes] |
145 | URLs count | [X] | [appropriate?] |
146 | Only indexable URLs | ✅/⚠️/❌ | [notes] |
147 | Includes priority | ✅/⚠️ | [notes] |
148 | Includes lastmod | ✅/⚠️ | [accurate?] |
149
150 **Issues Found**:
151 - [Issue 1]
152
153 ---
154
155 ### Crawl Budget Analysis
156
157 | Factor | Status | Impact |
158 |--------|--------|--------|
159 | Crawl errors | [X] errors | [Low/Med/High] |
160 | Duplicate content | [X] pages | [Low/Med/High] |
161 | Thin content | [X] pages | [Low/Med/High] |
162 | Redirect chains | [X] found | [Low/Med/High] |
163 | Orphan pages | [X] found | [Low/Med/High] |
164
165 **Crawlability Score**: [X]/10
166 ```
167
1682. **Audit Indexability**
169
170 ```markdown
171 ## Indexability Analysis
172
173 ### Index Status Overview
174
175 | Metric | Count | Notes |
176 |--------|-------|-------|
177 | Pages in sitemap | [X] | |
178 | Pages indexed | [X] | [source: site: search] |
179 | Index coverage ratio | [X]% | [good if >90%] |
180
181 ### Index Blockers Check
182
183 | Blocker Type | Found | Pages Affected |
184 |--------------|-------|----------------|
185 | noindex meta tag | [X] | [list or "none"] |
186 | noindex X-Robots | [X] | [list or "none"] |
187 | Robots.txt blocked | [X] | [list or "none"] |
188 | Canonical to other | [X] | [list or "none"] |
189 | 4xx/5xx errors | [X] | [list or "none"] |
190 | Redirect loops | [X] | [list or "none"] |
191
192 ### Canonical Tags Audit
193
194 | Check | Status | Notes |
195 |-------|--------|-------|
196 | Canonicals present | ✅/⚠️/❌ | [X]% of pages |
197 | Self-referencing | ✅/⚠️/❌ | [notes] |
198 | Consistent (HTTP/HTTPS) | ✅/⚠️/❌ | [notes] |
199 | Consistent (www/non-www) | ✅/⚠️/❌ | [notes] |
200 | No conflicting signals | ✅/⚠️/❌ | [notes] |
201
202 ### Duplicate Content Issues
203
204 | Issue Type | Count | Examples |
205 |------------|-------|----------|
206 | Exact duplicates | [X] | [URLs] |
207 | Near duplicates | [X] | [URLs] |
208 | Parameter duplicates | [X] | [URLs] |
209 | WWW/non-WWW | [X] | [notes] |
210 | HTTP/HTTPS | [X] | [notes] |
211
212 **Indexability Score**: [X]/10
213 ```
214
2153. **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
216
217 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the performance analysis template (Step 3).
218
2194. **Audit Mobile-Friendliness** — Mobile-friendly test, responsive design check, mobile-first indexing verification
220
221 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the mobile optimization template (Step 4).
222
2235. **Audit Security & HTTPS** — SSL certificate, HTTPS enforcement, mixed content, HSTS, security headers (CSP, X-Frame-Options, etc.)
224
225 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the security analysis template (Step 5).
226
2276. **Audit URL Structure** — URL patterns, issues (dynamic params, session IDs, uppercase), redirect analysis (chains, loops, 302s)
228
229 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the URL structure template (Step 6).
230
2317. **Audit Structured Data** — Schema markup validation, missing schema opportunities. CORE-EEAT alignment: maps to O05.
232
233 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the structured data template (Step 7).
234
2358. **Audit International SEO (if applicable)** — Hreflang implementation, language/region targeting
236
237 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the international SEO template (Step 8).
238
2399. **Generate Technical Audit Summary** — Overall health score with visual breakdown, critical/high/medium issues, quick wins, implementation roadmap (weeks 1-4+), monitoring recommendations
240
241 > **Reference**: See [references/technical-audit-templates.md](./references/technical-audit-templates.md) for the audit summary template (Step 9).
242
243## Validation Checkpoints
244
245### Input Validation
246- [ ] Site URL or domain clearly specified
247- [ ] Access to technical data (robots.txt, sitemap, or crawl results)
248- [ ] Performance metrics available (via ~~page speed tool or screenshots)
249
250### Output Validation
251- [ ] Every recommendation cites specific data points (not generic advice)
252- [ ] All issues include affected URLs or page counts
253- [ ] Performance metrics include actual numbers with units (seconds, KB, etc.)
254- [ ] Source of each data point clearly stated (~~web crawler data, ~~page speed tool, user-provided, or estimated)
255
256## Example
257
258> **Reference**: See [references/technical-audit-example.md](./references/technical-audit-example.md) for a full worked example (cloudhosting.com technical audit) and the comprehensive technical SEO checklist.
259
260## Tips for Success
261
2621. **Prioritize by impact** - Fix critical issues first
2632. **Monitor continuously** - Use ~~search console alerts
2643. **Test changes** - Verify fixes work before deploying widely
2654. **Document everything** - Track changes for troubleshooting
2665. **Regular audits** - Schedule quarterly technical reviews
267
268> **Technical reference**: For issue severity framework, prioritization matrix, and Core Web Vitals optimization quick reference, see [references/http-status-codes.md](./references/http-status-codes.md).
269
270## Reference Materials
271
272- [robots.txt Reference](./references/robots-txt-reference.md) — Syntax guide, templates, common configurations
273- [HTTP Status Codes](./references/http-status-codes.md) — SEO impact of each status code, redirect best practices
274- [Technical Audit Templates](./references/technical-audit-templates.md) — Detailed output templates for steps 3-9 (CWV, mobile, security, URL structure, structured data, international, audit summary)
275- [Technical Audit Example & Checklist](./references/technical-audit-example.md) — Full worked example and comprehensive technical SEO checklist
276
277## Related Skills
278
279- [on-page-seo-auditor](../on-page-seo-auditor/) — On-page SEO audit
280- [schema-markup-generator](../../build/schema-markup-generator/) — Fix schema issues
281- [performance-reporter](../../monitor/performance-reporter/) — Monitor improvements
282- [internal-linking-optimizer](../internal-linking-optimizer/) — Fix link issues
283- [alert-manager](../../monitor/alert-manager/) — Set up alerts for technical issues found
284- [content-quality-auditor](../../cross-cutting/content-quality-auditor/) — Full 80-item CORE-EEAT audit
285