Social Preview Inspector

Fetch any URL and extract og:*, twitter:*, <title>, and meta description tags with HTMLRewriter. Returns side-by-side preview validation for Twitter/X, Open Graph (Facebook/Slack), and Google search snippets, flagging missing required fields per platform.

Features

• GET /inspect - extract meta tags and validate per-platform preview requirements
• Side-by-side Twitter, Open Graph, and Google preview objects
• Flags missing and fallback fields (e.g. og:title used when twitter:title absent)

API Reference

GET /inspect

Fetch a page and return social preview validation for three platforms.

Example Request

curl "https://your-worker.workers.dev/inspect?url=https://example.com"

Success Response

{
  "url": "https://example.com/",
  "extracted": { "title": "Example", "description": "...", "openGraph": {}, "twitter": {} },
  "previews": {
    "openGraph": { "platform": "openGraph", "valid": true, "missing": [], "fields": {} },
    "twitter": { "platform": "twitter", "valid": false, "missing": ["image"], "fields": {} },
    "google": { "platform": "google", "valid": true, "missing": [], "fields": {} }
  }
}

Error Codes

• 400 - INVALID_URL
• 502 - FETCH_ERROR

Use Cases

• Debug why a link unfurls incorrectly on Slack, Twitter, or iMessage
• Audit marketing pages for missing Open Graph or Twitter Card tags
• Compare Google snippet fields against social preview metadata

Limitations

• Uses raw HTML fetch; does not execute JavaScript (client-rendered tags may be missing)
• Single URL per request; no batch inspection
• Platform validation rules are heuristic, not identical to each platform's renderer

Deployment

Local Development

cd apps/experiments/social-preview-inspector
npm install
npm run dev

Configuration

No bindings required beyond the Workers runtime.

Cloudflare Features Used

• Workers
• HTMLRewriter