seo-optimizer

SKILL.md

SEO Optimizer

Overview

Optimize websites for search engine visibility through technical SEO, on-page optimization, structured data implementation, and Core Web Vitals performance tuning. This skill covers crawlability, indexability, meta tag strategy, Schema.org markup, sitemap generation, canonical URL management, internationalization (hreflang), and performance optimization for Google's ranking signals.

Apply this skill whenever a site needs better organic search performance, whether for a single page audit or a full-site overhaul.

Multi-Phase Process

Phase 1: Technical Audit

  1. Crawl the site (Screaming Frog, Sitebulb, or custom script)
  2. Check robots.txt and XML sitemap validity
  3. Identify crawl errors, redirect chains, and broken links
  4. Verify canonical URLs and duplicate content handling
  5. Assess mobile-friendliness and responsive design
  6. Check HTTPS implementation and mixed content
  7. Evaluate page load performance (Core Web Vitals)

STOP — Do NOT proceed to Phase 2 until audit findings are documented and prioritized.

Phase 2: On-Page Optimization

  1. Audit title tags (unique, 50-60 chars, keyword placement)
  2. Review meta descriptions (unique, 150-160 chars, compelling CTAs)
  3. Analyze heading hierarchy (single H1, logical H2-H6 structure)
  4. Optimize image alt text and file names
  5. Review internal linking structure and anchor text
  6. Check URL structure (short, descriptive, hyphenated)
  7. Validate Open Graph and Twitter Card tags

STOP — Do NOT proceed to Phase 3 until on-page changes are implemented and verified.

Phase 3: Structured Data Implementation

  1. Identify applicable Schema.org types for content
  2. Implement JSON-LD structured data
  3. Validate with Google Rich Results Test
  4. Test for rich snippet eligibility
  5. Monitor Search Console for structured data errors

STOP — Do NOT proceed to Phase 4 until structured data passes validation.

Phase 4: Monitoring and Iteration

  1. Set up Google Search Console monitoring
  2. Track Core Web Vitals over time
  3. Monitor indexation status and coverage
  4. Review search performance (clicks, impressions, CTR, position)
  5. Set up alerts for crawl errors and ranking drops

Audit Priority Decision Table

Finding Severity Fix Priority Impact
No HTTPS / mixed content Critical Immediate Ranking penalty, trust signals
Missing canonical URLs Critical Immediate Duplicate content dilution
Broken redirect chains (3+ hops) High This sprint Crawl budget waste, link equity loss
Missing or duplicate title tags High This sprint CTR drop, ranking confusion
No structured data Medium Next sprint Missing rich snippets
Missing alt text on images Medium Next sprint Accessibility and image search loss
Suboptimal Core Web Vitals Medium Next sprint Ranking signal, user experience
Missing hreflang tags (multi-language) Low Backlog Geo-targeting issues
Non-descriptive URL slugs Low Backlog Minor ranking and CTR effect

Meta Tag Reference

Essential Meta Tags

<head>
  <!-- Primary -->
  <title>Primary Keyword - Secondary Keyword | Brand Name</title>
  <meta name="description" content="Compelling 150-160 char description with target keyword and clear value proposition.">
  <link rel="canonical" href="https://example.com/page">

  <!-- Robots -->
  <meta name="robots" content="index, follow">
  <!-- or noindex, nofollow for pages that shouldn't be indexed -->

  <!-- Viewport (mobile) -->
  <meta name="viewport" content="width=device-width, initial-scale=1">

  <!-- Open Graph -->
  <meta property="og:type" content="website">
  <meta property="og:title" content="Page Title for Social Sharing">
  <meta property="og:description" content="Description optimized for social sharing.">
  <meta property="og:image" content="https://example.com/og-image.jpg">
  <meta property="og:url" content="https://example.com/page">
  <meta property="og:site_name" content="Brand Name">

  <!-- Twitter Card -->
  <meta name="twitter:card" content="summary_large_image">
  <meta name="twitter:title" content="Page Title">
  <meta name="twitter:description" content="Twitter-optimized description.">
  <meta name="twitter:image" content="https://example.com/twitter-image.jpg">

  <!-- Internationalization -->
  <link rel="alternate" hreflang="en" href="https://example.com/en/page">
  <link rel="alternate" hreflang="de" href="https://example.com/de/page">
  <link rel="alternate" hreflang="x-default" href="https://example.com/page">
</head>

Meta Tag Optimization Matrix

Element Max Length Priority Keywords Common Mistakes
Title tag 50-60 chars Front-load primary keyword Too long, keyword stuffing, duplicate
Meta description 150-160 chars Include CTA and keyword Missing, duplicate, no CTA
H1 N/A (single per page) Primary keyword variation Multiple H1s, missing H1
URL slug 3-5 words Target keyword Too long, parameters, underscores
Image alt 125 chars Descriptive, keyword if natural Empty, "image of...", keyword stuffing
OG title 60-90 chars Engaging, shareable Same as title tag (missed opportunity)

Structured Data (JSON-LD)

Article

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "How to Optimize Core Web Vitals",
  "author": {
    "@type": "Person",
    "name": "Jane Smith",
    "url": "https://example.com/authors/jane-smith"
  },
  "datePublished": "2026-03-01",
  "dateModified": "2026-03-15",
  "image": "https://example.com/images/article-hero.jpg",
  "publisher": {
    "@type": "Organization",
    "name": "Example Blog",
    "logo": {
      "@type": "ImageObject",
      "url": "https://example.com/logo.png"
    }
  },
  "description": "A comprehensive guide to improving LCP, FID, and CLS scores."
}
</script>

Product

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Product",
  "name": "Widget Pro",
  "description": "Professional-grade widget for enterprise use.",
  "image": "https://example.com/widget-pro.jpg",
  "brand": { "@type": "Brand", "name": "WidgetCo" },
  "offers": {
    "@type": "Offer",
    "price": "49.99",
    "priceCurrency": "USD",
    "availability": "https://schema.org/InStock",
    "url": "https://example.com/widget-pro"
  },
  "aggregateRating": {
    "@type": "AggregateRating",
    "ratingValue": "4.7",
    "reviewCount": "312"
  }
}
</script>

FAQ Page

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "What is Core Web Vitals?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Core Web Vitals are a set of metrics that measure real-world user experience for loading, interactivity, and visual stability."
      }
    }
  ]
}
</script>

Schema Type Decision Guide

Content Type Schema Type Rich Result
Blog post Article Article snippet
Product page Product Price, rating, availability
FAQ section FAQPage Expandable Q&A
How-to guide HowTo Step-by-step snippet
Recipe Recipe Image, time, rating
Event Event Date, location, price
Local business LocalBusiness Map pack, hours
Software SoftwareApplication Rating, price
Breadcrumbs BreadcrumbList Breadcrumb trail
Video VideoObject Thumbnail, duration

Core Web Vitals

Metrics and Thresholds

Metric Good Needs Improvement Poor Measures
LCP (Largest Contentful Paint) <= 2.5s <= 4.0s > 4.0s Loading performance
INP (Interaction to Next Paint) <= 200ms <= 500ms > 500ms Interactivity
CLS (Cumulative Layout Shift) <= 0.1 <= 0.25 > 0.25 Visual stability

LCP Optimization

<!-- Preload hero image -->
<link rel="preload" as="image" href="/hero.webp" fetchpriority="high">

<!-- Use modern image formats -->
<picture>
  <source srcset="/hero.avif" type="image/avif">
  <source srcset="/hero.webp" type="image/webp">
  <img src="/hero.jpg" alt="Hero description" width="1200" height="600"
       fetchpriority="high" decoding="async">
</picture>

CLS Prevention

/* Always set dimensions on images and video */
img, video {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
}

/* Reserve space for dynamic content */
.ad-slot {
  min-height: 250px;
}

/* Avoid inserting content above existing content */
.notification-bar {
  position: fixed; /* doesn't shift layout */
}

INP Optimization

// Break long tasks with yield
async function processLargeDataset(data) {
  for (let i = 0; i < data.length; i++) {
    processItem(data[i]);
    if (i % 100 === 0) {
      await new Promise(resolve => setTimeout(resolve, 0)); // yield to main thread
    }
  }
}

// Use requestIdleCallback for non-critical work
requestIdleCallback(() => {
  loadAnalytics();
  initNonCriticalFeatures();
});

XML Sitemap

Generation Pattern

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://example.com/</loc>
    <lastmod>2026-03-15</lastmod>
    <changefreq>daily</changefreq>
    <priority>1.0</priority>
  </url>
  <url>
    <loc>https://example.com/products</loc>
    <lastmod>2026-03-14</lastmod>
    <changefreq>weekly</changefreq>
    <priority>0.8</priority>
  </url>
</urlset>

Sitemap Best Practices

  • Maximum 50,000 URLs per sitemap file
  • Use sitemap index for larger sites
  • Include only canonical, indexable URLs
  • Update lastmod only when content genuinely changes
  • Submit via Google Search Console and robots.txt

robots.txt Template

User-agent: *
Allow: /
Disallow: /admin/
Disallow: /api/
Disallow: /search?
Disallow: /*?sort=
Disallow: /*?filter=

Sitemap: https://example.com/sitemap.xml

Next.js / React SEO Patterns

Next.js Metadata API (App Router)

import type { Metadata } from 'next';

export const metadata: Metadata = {
  title: {
    template: '%s | Brand Name',
    default: 'Brand Name - Tagline',
  },
  description: 'Site-wide default description.',
  openGraph: {
    type: 'website',
    locale: 'en_US',
    url: 'https://example.com',
    siteName: 'Brand Name',
  },
  twitter: {
    card: 'summary_large_image',
  },
  robots: {
    index: true,
    follow: true,
  },
  alternates: {
    canonical: 'https://example.com',
  },
};

Dynamic Metadata per Page

export async function generateMetadata({ params }): Promise<Metadata> {
  const product = await getProduct(params.slug);

  return {
    title: product.name,
    description: product.description.slice(0, 160),
    openGraph: {
      title: product.name,
      description: product.description.slice(0, 200),
      images: [{ url: product.image, width: 1200, height: 630 }],
    },
  };
}

Anti-Patterns / Common Mistakes

Anti-Pattern Why It Fails What To Do Instead
Keyword stuffing in titles/content Triggers spam filters, reduces CTR Use primary keyword once naturally, add variations
Same title/description across pages Duplicate content signals, wasted opportunity Unique, page-specific meta for every indexable URL
Blocking CSS/JS in robots.txt Googlebot cannot render pages Allow all rendering resources
Structured data mismatching page content Google penalties, rich snippet removal Schema must reflect visible content exactly
Redirect chains > 2 hops Crawl budget waste, link equity loss Redirect directly to final destination
JS-only navigation without SSR links Crawler cannot discover pages Server-render navigation links
Ignoring Core Web Vitals Ranking signal degradation Profile and optimize LCP, INP, CLS
Missing canonical URLs Duplicate content penalties Set canonical on every indexable page
Over-optimized anchor text Unnatural link patterns trigger penalties Use descriptive, varied anchor text
Hiding content with CSS for SEO Cloaking violation All SEO content must be visible to users

Anti-Rationalization Guards

  • Do NOT skip the technical audit because "the site looks fine" -- crawl it.
  • Do NOT add structured data without validating it passes the Rich Results Test.
  • Do NOT assume meta tags are correct without checking every page type.
  • Do NOT deploy SEO changes without before/after measurement.
  • Do NOT optimize for search engines at the expense of user experience.

Integration Points

Skill How It Connects
content-creator SEO informs keyword targeting and headline strategy for marketing content
content-research-writer Research-backed content needs SEO-optimized structure and meta tags
senior-frontend Core Web Vitals optimization requires frontend performance tuning
performance-optimization Page speed directly affects LCP and INP scores
deployment SEO changes need proper cache invalidation and redirect configuration
tech-docs-generator Documentation sites need sitemap, canonical, and structured data setup

Skill Type

FLEXIBLE — Adapt the optimization strategy to the site's technology stack, content type, and competitive landscape. Technical SEO fundamentals and structured data best practices are strongly recommended; specific implementation patterns vary by framework.

Weekly Installs
5
First Seen
Today
Installed on
amp4
cline4
opencode4
cursor4
kimi-cli4
warp4