F9XR's SEO CodeBase Auditor SKILL

24 SEO Pillars.
One Command.

Drop a single file into any codebase, run one prompt, and get a production-ready SEO audit across 24 pillars - from technical crawlability to semantic entity analysis to YouTube SEO. Every finding includes the exact fix.

Download SKILL.md View on GitHub
seo_audit_report.md
#PillarIssueSeverityFix
1On-PageMissing title tagCriticalAdd <title> to <head>
2TechnicalNo canonical on /blog/HighAdd rel="canonical"
3PerformanceImages missing dimensionsHighAdd w/h attributes
4SchemaMissing VideoObjectMediumAdd JSON-LD block
5SemanticKeyword density <0.5%MediumExpand topical coverage
# Fix: Add meta description to index.html:21 <meta name="description" content="Enterprise SEO auditing ...">
Audit Scope

24 Audit Pillars

Every check is context-aware - a portfolio site and an e-commerce store never receive the same audit. Pillars are weighted by project type.

Technical Foundation
01
On-Page SEO
Title tags, meta descriptions, heading hierarchy, anchor text, SERP snippets, viewport, charset, language, table optimization, external link quality.
02
Technical SEO
Indexability matrix, crawl budget, structured data validation, redirect chains, soft 404s, compression, caching, CDN, server response, duplicate detection.
03
Performance (CWV)
LCP, FCP, CLS, INP, TTFB - scored against Google thresholds with mobile/desktop splits. Image optimization, font loading, DOM complexity, preload strategies.
04
URL Structure & Architecture
Hierarchy, slug format, trailing slash consistency, pagination, silo architecture, orphan detection, redirect chain static analysis.
05
Mobile SEO
Viewport configuration, responsive design, touch target sizing, font legibility, mobile-first structured data, interstitial detection.
06
Image SEO
Alt text, WebP/AVIF format, responsive images, lazy loading, file name SEO, image sitemap, dimension attributes for CLS prevention.
09
XML Sitemap & Robots.txt
Sitemap structure & coverage, robots.txt validation, IndexNow protocol setup with key file hosting and HTTP POST submission.
Content & Authority
07
Semantic SEO & Content
Search intent mapping, keyword density calculation, entity salience, knowledge graph alignment, passage optimization, topic clustering, information gain scoring.
08
Internal Linking & Equity
Orphan detection, link depth, breadcrumb schema, link equity silos, anchor text diversity, navigation structure audit.
14
Blog & Content SEO
Article schema, author attribution, pagination, related content, category SEO, reading time, table of contents, content freshness.
16
E-E-A-T Signals
Experience assessment, author transparency, About/Contact pages, external citations, content credibility, YMYL compliance, brand authority, reputation audit.
17
Rich Results Eligibility
Opportunity map for 16+ rich result types, required field validation, publisher logo, carousel eligibility, rich result testing URLs.
18
AI / SGE / Voice Search
AI overview extraction readiness, conversational keyword coverage, featured snippet targeting, voice search optimization, QA fragment structuring, plain language scoring.
Platform & Process
13
E-Commerce SEO
Product/Review schema, availability status, price format, category pages, faceted navigation, breadcrumb, product image SEO.
15
JavaScript Framework SEO
Next.js/Nuxt/Astro/SPA-specific checks: SSR vs CSR, dynamic metadata, image/link components, hydration strategy, middleware crawlability.
19
CI/CD & Automation
Pre-commit hooks, GitHub Actions workflow, GitLab CI template, lighthouse-ci, scheduled audits, Slack alerts, deploy hooks.
20
Migration SEO
URL mapping verification, redirect chain depth, canonical conflicts, domain change checklist, content migration fidelity, post-migration validation.
21
Content Pruning
Thin/duplicate/orphan detection, consolidation strategy (merge/rewrite/remove/noindex), crawl budget recovery, redirect cleanup, index bloat assessment.
22
Third-Party Script Audit
Script inventory, critical path impact, tag manager audit, chat/ad widget analysis, consent mode, waterfall analysis, performance budget recommendation.
Specialized
10
Social & Regional SEO
Open Graph, Twitter Cards, hreflang, local business schema, NAP consistency, geo-targeting, GBP recommendations.
11
Security SEO
HTTPS enforcement, mixed content detection, HSTS recommendation, form security, external link security (noopener/noreferrer).
12
Accessibility SEO
ARIA landmarks, form labels, focus order, color contrast, skip navigation, video captions, empty interactive elements.
23
Competitor Analysis
Content depth comparison, keyword gap analysis, entity coverage, SERP feature ownership, schema adoption, technical benchmarking, strategic recommendations.
24
Video & YouTube SEO
VideoObject schema, embed best practices, transcript SEO, thumbnail optimization, video sitemap, rich result eligibility, performance impact.
+
IndexNow Protocol
Built into Pillar 9 - key file hosting, HTTP POST submission via api.indexnow.org, curl test command, rapid indexation setup.
Process

Five-Pass Audit Workflow

The skill works in distinct passes, never combining steps. Each pass has a specific job, from workspace discovery to self-critique before delivery.

1
Discover
Map the file tree, scan config files, detect routing framework, discover all URLs, build indexability matrix, flag orphan & unreachable pages.
2
Analyze
Evaluate every file against relevant pillars. Suppress irrelevant checks - no JS Framework SEO for static HTML, no Blog SEO for sites without a blog.
3
Prioritize
Sort findings by severity then traffic impact. Cap the Priority Fix Matrix at 20 items - anything beyond that is noise until critical items are resolved.
4
Report
Generate seo_audit_report.md with the exact output blueprint - executive summary, priority matrix, granular pillar evaluations with current code + fix blocks.
5
Critique
Review as if you were a competitor's SEO lead. Every severity label, root cause, and fix must be defensible. Remove one finding before delivering.
Deliverable

Complete Audit Report

Every run generates a production-grade seo_audit_report.md and CSV export with the Priority Fix Matrix, per-pillar evaluations, revenue impact estimates, and copy-paste-ready fix blocks.

Priority Fix Matrix

# Pillar Issue Severity File Effort Traffic Impact Fix Type
1 On-Page Missing unique H1 tag High /about.html S +5-10% metadata
2 Performance Images missing dimensions High /index.html:45 M +3-8% performance
3 Schema Missing Product markup Critical /products/*.html M +8-15% schema
4 Video VideoObject schema missing Medium /watch/*.html S +2-5% schema
5 Semantic Entity coverage gap Medium /blog/*.html L +3-7% content

Granular Pillar Evaluation

### Pillar 1 - On-Page SEO Files Audited: index.html, about.html, contact.html, blog/index.html Issue: Missing title tag on about.html Severity: Critical Current Code: <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width"> </head> Fix - Add title tag: <head> <meta charset="utf-8"> <title>About Us - Brand Name</title> <meta name="viewport" content="width=device-width"> </head>
Philosophy

Why This Approach Works

Most AI-generated SEO audits produce noise. This skill is designed to produce signal - every finding is defensible, prioritized, and includes the exact fix.

Evidence Over Opinion
Every finding cites a specific Google guideline, ranking factor, or schema.org specification. If the rule can't be cited, the issue is not raised.
The Fix Is the Deliverable
Users don't want a diagnosis - they want the corrected code block they can paste and deploy. Every flagged issue includes the exact replacement.
Context-Aware Criteria
A portfolio site doesn't need Product schema. A local bakery missing NAP consistency is Critical. Severity is a function of impact, not issue count.
Quick Start

One-Liner Prompts

Drop F9XR's SEO CodeBase Auditor SKILL into any project root, then run any of these prompts in Cursor, Copilot, Claude, or any AI chat interface. See the demo audit report for a sample output.

Full Audit
@SKILL.md Run a comprehensive full-stack SEO audit across all files in this workspace. Generate seo_audit_report.md and seo_audit_report.csv with all 24 pillars evaluated.
On-Page
@SKILL.md Run a title tag and meta description optimization audit. Check every page for missing titles, short descriptions, and duplicate metadata.
Performance
@SKILL.md Run a Core Web Vitals audit across LCP, FCP, CLS, INP, and TTFB. Split findings by mobile vs desktop.
Competitors
@SKILL.md Run a competitive SEO gap analysis against [competitor1.com, competitor2.com]. Compare content depth, entity coverage, schema adoption, and keyword positioning.
Video
@SKILL.md Run a Video & YouTube SEO audit. Catalog all video embeds, verify VideoObject schema, check embed best practices, and assess rich result eligibility.
Migration
@SKILL.md Run a migration SEO readiness check. Assume we are migrating from [old-domain] to [new-domain]. Flag all items that will break post-migration.
Technical
@SKILL.md Run an IndexNow readiness audit. Check if IndexNow key file exists, verify HTTP POST submission format, and provide the exact curl command.
Get Started

Ready to ship SEO-safe code?

Download F9XR's SEO CodeBase Auditor SKILL, drop it in your project root, and run one prompt. No setup, no config, no subscriptions.

Download SKILL.md View on GitHub →