SEO Analyzer

Static SEO analysis for HTML files using cheerio-based parsing. Validates meta tags, social media tags, heading structure, and structured data. Also includes keyword analysis for content optimization.

Analysis Workflow

1. Parse HTML with cheerio
2. Check Critical Issues (P0):

- Title tag presence and length - Meta description presence and length - Single H1 tag - Canonical URL

1. Check Important Issues (P1):

- Robots meta directives - Viewport meta - Heading hierarchy - Lang attribute

1. Check Recommended (P2):

- Open Graph tags - Twitter Cards - JSON-LD structured data - Hreflang tags

1. Generate Report with issues and recommendations

Usage

Installation

cd ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer
npm install
npm run build

Run Analysis

# SEO analysis (default)
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/src/index.ts path/to/file.html

# SEO analysis with JSON output
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/src/index.ts path/to/file.html --json

# Keyword analysis
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/src/index.ts path/to/file.html --keywords

# Both SEO and Keyword analysis
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/src/index.ts path/to/file.html --both

# Combined with JSON output
npx tsx ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/src/index.ts path/to/file.html --both --json

Using Built Version

# After npm run build
node ${CLAUDE_PLUGIN_ROOT}/skills/seo-analyzer/dist/index.js path/to/file.html

Check Items

P0 - Critical (Indexing/Ranking Impact)

P1 - Important (SEO Quality)

P2 - Recommended (Social/Rich Results)

Output Format

Text Report

# SEO Analysis Report: index.html

## Summary
- Critical: 1
- Important: 2
- Recommended: 3
- Passed: 8

## Critical Issues (P0)

### 1. Missing Meta Description
**Check**: meta-description
**Fix**: Add <meta name="description" content="Your description here">

## Important Issues (P1)
...

JSON Output

{
  "file": "index.html",
  "timestamp": "2024-01-15T10:00:00Z",
  "confidence": 100,
  "summary": {
    "critical": 1,
    "important": 2,
    "recommended": 3,
    "passed": 8
  },
  "issues": [
    {
      "severity": "critical",
      "check": "meta-description",
      "message": "Missing meta description",
      "fix": "Add <meta name=\"description\" content=\"...\">"
    }
  ],
  "passed": [
    {
      "check": "title",
      "value": "Page Title - Brand",
      "length": 18
    }
  ],
  "warnings": []
}

Detection Features

React/SPA Detection

The analyzer detects client-side rendered applications and adjusts confidence:

• Presence of #root or #app container
• React/Vue/Angular script references
• Empty body with JavaScript bundles

When detected, a warning is added that static analysis may not reflect the rendered page.

Keyword Analysis

The keyword analyzer extracts and scores keywords:

npx tsx src/index.ts file.html --keywords

Outputs:

• Primary keywords by score
• Key phrases (2-word combinations)
• Keyword density
• Placement analysis (title, H1, description)
• Recommendations for improvement

Keyword Report Example

# Keyword Analysis: index.html

## Stats
- Total words: 1245
- Unique words: 342

## Primary Keywords (by score)

| Keyword | Score | Freq | Title | H1 | Description |
|---------|-------|------|-------|----|-----------:|
| product | 28 | 15 | Y | Y | Y |
| service | 21 | 12 | Y |   | Y |
...

## Recommendations

- Consider adding "product management" to your title tag

Integration with Lookup

For detailed guidance on any issue, reference the seo-lookup skill:

# Look up og:image requirements
cat ${CLAUDE_PLUGIN_ROOT}/skills/seo-lookup/seo-index.json | jq '.["og-tags"]["og:image"]'

# Look up Article schema
cat ${CLAUDE_PLUGIN_ROOT}/skills/seo-lookup/structured-data-index.json | jq '.schemas.Article'

External Validation

After fixing issues, validate with:

• Google Rich Results Test
• Facebook Sharing Debugger
• Twitter Card Validator