
Seo Technical
- 35 installs
- 548 repo stars
- Updated July 20, 2026
- agricidaniel/codex-seo
seo-technical is a Claude Code skill that runs a technical SEO audit across 9 categories including crawlability, Core Web Vitals, and IndexNow.
About
seo-technical is a Claude Code skill that runs a technical SEO audit across nine categories: crawlability, indexability, security, URL structure, mobile, Core Web Vitals, structured data, JavaScript rendering, and IndexNow. It checks robots.txt, canonical tags, HTTPS and security headers, mobile-first readiness, and current Core Web Vitals thresholds. It also advises on managing AI crawlers like GPTBot and ClaudeBot. A developer uses it to find and prioritize technical issues blocking indexing or ranking.
- Audits technical SEO across 9 categories from crawlability to IndexNow
- Covers Core Web Vitals thresholds (LCP, INP, CLS) with current 2026 guidance
- Manages AI crawlers (GPTBot, ClaudeBot, PerplexityBot) via robots.txt
Seo Technical by the numbers
- 35 all-time installs (skills.sh)
- Ranked #1,384 of 1,879 Marketing & SEO skills by installs in the Skillselion catalog
- Data as of Aug 5, 2026 (Skillselion catalog sync)
seo-technical capabilities & compatibility
- Capabilities
- seo audit · core web vitals audit · crawlability audit · robots audit
- Use cases
- seo
- Pricing
- Free
What seo-technical says it does
Technical SEO audit across 9 categories: crawlability, indexability, security,
**LCP** (Largest Contentful Paint): target <2.5s
INP replaced FID on March 12, 2024.
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| Installs | 35 |
|---|---|
| repo stars | ★ 548 |
| Last updated | July 20, 2026 |
| Repository | agricidaniel/codex-seo ↗ |
What it does
Run a nine-category technical SEO audit of a site covering crawlability, Core Web Vitals, security headers, and AI-crawler rules.
Who is it for?
Finding and prioritizing technical issues that block indexing or ranking
Skip if: Content strategy or keyword research, which are separate skills
When should I use this skill?
user says technical SEO, crawl issues, robots.txt, Core Web Vitals, site speed, or security headers
What you get
A prioritized technical SEO audit across 9 categories with severity-ranked fixes.
- technical SEO audit report
- severity-ranked issue list
By the numbers
- Audits technical SEO across 9 categories
- Lists 7 known AI crawlers with robots.txt tokens
Files
Technical SEO Audit
Shared Data Cache
Step 0 -- Check shared data cache:
Before gathering, check .seo-cache/ for reusable context from related SEO skills. Reference: ../seo/references/shared-data-cache.md for schemas and dependency map.
Check these cache files when present:
.seo-cache/site-meta.jsonfor domain, business type, industry, and crawl context.seo-cache/audit-scores.jsonfor prior full-audit priorities.seo-cache/pages/{url-slug}/page-analysis.jsonfor page-level context when a URL is provided
- If found: parse and use clearly valid fields (note "Using cached [X] from [date]")
- If missing, corrupt, or irrelevant: continue with fresh evidence
- If the user says "refresh" or "re-run": ignore cache reads and overwrite on write
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:
| Crawler | Company | robots.txt token | Purpose |
|---|---|---|---|
| GPTBot | OpenAI | GPTBot | Model training |
| ChatGPT-User | OpenAI | ChatGPT-User | Real-time browsing |
| ClaudeBot | Anthropic | ClaudeBot | Model training |
| PerplexityBot | Perplexity | PerplexityBot | Search index + training |
| Bytespider | ByteDance | Bytespider | Model training |
| Google-Extended | Google-Extended | Gemini training (NOT search) | |
| CCBot | Common Crawl | CCBot | Open dataset |
Key distinctions:
- Blocking
Google-Extendedprevents Gemini training use but does NOT affect Google Search indexing or AI Overviews (those useGooglebot) - Blocking
GPTBotprevents 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
| Category | Status | Score |
|---|---|---|
| Crawlability | pass/warn/fail | XX/100 |
| Indexability | pass/warn/fail | XX/100 |
| Security | pass/warn/fail | XX/100 |
| URL Structure | pass/warn/fail | XX/100 |
| Mobile | pass/warn/fail | XX/100 |
| Core Web Vitals | pass/warn/fail | XX/100 |
| Structured Data | pass/warn/fail | XX/100 |
| JS Rendering | pass/warn/fail | XX/100 |
| IndexNow | pass/warn/fail | XX/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
| Scenario | Action |
|---|---|
| URL unreachable | Report connection error with status code. Suggest verifying URL, checking DNS resolution, and confirming the site is publicly accessible. |
| robots.txt not found | Note that no robots.txt was detected at the root domain. Recommend creating one with appropriate directives. Continue audit on remaining categories. |
| HTTPS not configured | Flag as a critical issue. Report whether HTTP is served without redirect, mixed content exists, or SSL certificate is missing/expired. |
| Core Web Vitals data unavailable | Note 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. |
Write to shared data cache
After completing all work, write a concise JSON summary to .seo-cache/ when the workflow produced durable findings. Use the schemas and naming rules in ../seo/references/shared-data-cache.md; include at least cache_type, analyzed_at, source URL/domain, key findings, issues, recommendations, and tool limitations. Add .seo-cache/ to .gitignore if it is missing.
MIT License - see repository root LICENSE file for complete terms.
Copyright (c) 2026 AgriciDaniel
https://github.com/AgriciDaniel/codex-seo
Related skills
FAQ
How many categories does seo-technical audit?
Nine: crawlability, indexability, security, URL structure, mobile, Core Web Vitals, structured data, JavaScript rendering, and IndexNow.
Which Core Web Vitals metric does it use instead of FID?
INP (Interaction to Next Paint), since INP replaced FID on March 12, 2024.