Seo Audit
Audit landing and marketing pages against 2026 Core Web Vitals thresholds with pass, warn, and fail scoring for SEO health checks.
Overview
SEO Audit is an agent skill for the Launch phase that scores page health against Core Web Vitals thresholds (LCP, CLS, INP) for technical SEO audits.
Install
npx skills add https://github.com/alirezarezvani/claude-skills --skill seo-auditWhat is this skill?
- Documents three Core Web Vitals: LCP, CLS, and INP with Good / Needs Improvement / Poor bands (2026 CrUX reference)
- Maps each metric to pass, warn, and fail states for automated seo_health_scorer-style workflows
- Lists concrete fixes: image preload/WebP, TTFB, render-blocking JS, explicit dimensions, font-display, long-task splitti
- Distinguishes field data (28-day CrUX p75) vs lab data (Lighthouse, PageSpeed)
- Performance category reference aligned with Google’s published CWV methodology
- 3 Core Web Vitals metrics: LCP, CLS, INP
- LCP Good ≤ 2.5s; CLS Good ≤ 0.1; INP Good ≤ 200ms
- CrUX field data uses a 28-day rolling p75
Adoption & trust: 545 installs on skills.sh; 17.5k GitHub stars; 2/3 security scanners passed (skills.sh audits).
What problem does it solve?
Your marketing site is live but you do not know whether performance and stability metrics meet Google’s Good thresholds or what to fix first.
Who is it for?
Solo builders shipping landing pages, docs sites, or storefronts who need a consistent CWV checklist tied to SEO scoring scripts.
Skip if: Early Validate wireframes with no URL yet—run this after you have deployable pages and measurable CrUX or Lighthouse data.
When should I use this skill?
Run a technical SEO or performance health check against documented Core Web Vitals thresholds before or after launch.
What do I get? / Deliverables
You get threshold-aligned pass/warn/fail labels per CWV metric plus prioritized remediation bullets before broader launch or growth spend.
- Per-metric pass, warn, or fail classification against CWV bands
- Prioritized fix list keyed to LCP, CLS, or INP failures
- Note on field (CrUX) vs lab measurement source
Recommended Skills
Journey fit
Launch is when indexed pages must meet Google UX signals; this skill is a technical SEO performance checker, not a pre-build architecture guide. SEO subphase covers organic discovery quality; CWV thresholds directly affect rankings and snippet eligibility post-launch.
How it compares
Skill-pack reference thresholds and fixes—not a hosted MCP lighthouse server or one-click CI integration by itself.
Common Questions / FAQ
Who is seo-audit for?
Indie devs and marketers using agent-assisted SEO reviews who need authoritative LCP, CLS, and INP cutoffs for scoring pipelines.
When should I use seo-audit?
At Launch during SEO hardening, before major distribution pushes, and in Grow when organic traffic stalls and you suspect CWV regressions.
Is seo-audit safe to install?
It is reference documentation for audit logic; confirm upstream script behavior and review the Security Audits panel on this Prism page before enabling network or browser automation alongside it.
SKILL.md
READMESKILL.md - Seo Audit
# Core Web Vitals Thresholds (2026) Reference for `seo_health_scorer.py` and the Performance category. Updated per Google's CrUX methodology. ## The three metrics | Metric | Good | Needs Improvement | Poor | What it measures | |---|---|---|---|---| | **LCP** (Largest Contentful Paint) | ≤ 2.5s | 2.5s – 4.0s | > 4.0s | Loading speed — when the main content is visible | | **CLS** (Cumulative Layout Shift) | ≤ 0.1 | 0.1 – 0.25 | > 0.25 | Visual stability — unexpected layout jumps | | **INP** (Interaction to Next Paint) | ≤ 200ms | 200ms – 500ms | > 500ms | Responsiveness — delay after user interaction | ## Scoring mapping ``` pass = metric in "Good" range warn = metric in "Needs Improvement" range fail = metric in "Poor" range ``` ## Common fixes by metric ### LCP > 2.5s - Optimize largest image (WebP/AVIF, proper sizing, preload) - Reduce server response time (TTFB < 800ms) - Remove render-blocking CSS/JS - Use CDN for static assets ### CLS > 0.1 - Set explicit width/height on images and video - Reserve space for ads/embeds before load - Avoid inserting content above the fold after page load - Use `font-display: swap` for web fonts ### INP > 200ms - Break up long tasks (> 50ms) into smaller chunks - Defer non-critical JavaScript - Use `requestIdleCallback` for low-priority work - Minimize main-thread blocking from third-party scripts ## Measurement sources - **Field data:** CrUX (Chrome User Experience Report) — 28-day rolling p75 - **Lab data:** Lighthouse, PageSpeed Insights — synthetic, not real users - **Monitoring:** web-vitals.js library for RUM (Real User Monitoring) Field data (CrUX) is what Google uses for ranking signals. Lab data helps debug but doesn't directly affect rankings. # E-E-A-T Framework Reference Experience, Expertise, Authoritativeness, Trustworthiness — Google's quality rater guidelines framework for evaluating content quality. Updated per September 2025 Quality Rater Guidelines. ## The four signals | Signal | What it means | How to demonstrate | |---|---|---| | **Experience** | First-hand experience with the topic | Personal anecdotes, original photos, usage details, "I tested this" | | **Expertise** | Demonstrable knowledge or skill | Credentials, detailed technical depth, accurate terminology | | **Authoritativeness** | Recognition by others in the field | Backlinks from authoritative sites, citations, brand mentions | | **Trustworthiness** | Accuracy, transparency, safety | HTTPS, clear authorship, sources cited, contact info, privacy policy | **Trust** is the most important — it encompasses the other three. A page can have expertise but lose trust through misleading claims. ## Audit checklist ### Experience signals - [ ] Author has demonstrable experience with the topic - [ ] Content includes first-hand observations (not just research summaries) - [ ] Original images or screenshots (not stock photos) - [ ] Specific details that only come from experience ### Expertise signals - [ ] Author bio with relevant credentials - [ ] Content depth matches topic complexity (YMYL topics need more) - [ ] Accurate, up-to-date information - [ ] Proper use of domain terminology ### Authoritativeness signals - [ ] Site is recognized in its niche (backlink profile) - [ ] Author has published elsewhere on this topic - [ ] Content is cited by other authoritative sources - [ ] Organization has relevant credentials/certifications ### Trustworthiness signals - [ ] HTTPS enforced - [ ] Clear author attribution (name, bio, photo) - [ ] Sources cited with links - [ ] Contact information accessible - [ ] Privacy policy present - [ ] No misleading claims or clickbait - [ ] Content reviewed or updated regularly (dateModified) ## YMYL topics (Your Money or Your Life) Topics that could impact health, safety, financial stability, or well-being require **higher E-E-A-T standards**: - Health and medical information - Financial advice and transactions - Legal information - News and current events - Safety-rel