SEO Lens

Browser extension that audits SEO metadata on any webpage. Instant, actionable feedback on title, meta tags, headings, structured data, and more — with every finding copyable as structured plain text for AI coding agents (Claude Code, Cursor, Copilot).

Features

• Live audit pipeline driven by the active tab. Re-runs on tab switch, window focus, full load, SPA soft-nav, or manual refresh.
• Crawler-accurate fetch. Background service worker fetches the active tab's URL and parses with DOMParser, matching what a crawler sees (not the rendered SPA DOM).
• Rules coverage. Title, meta description, headings (single H1, skip-level), image alt, structured data (schema.org recognition, rich-results validation, recommendations), social OG/Twitter, canonical, robots directives.
• Side panel UI with two tabs:
  • Audit — overall score, severity counts, per-category scores, filterable findings list with per-finding copy (grep-able snippets), share-as-image card, Markdown/JSON export.
  • Metadata — meta, social preview, heading tree, JSON-LD blocks, breadcrumbs, indexing dashboard, site-level signals, image gallery.
• Copy-for-AI. Per-finding copy, per-section copy in Metadata, full-report exports.

Monorepo

apps/
  extension/    Chrome extension (WXT + React, shipped)
  web/          Landing page (Next.js, scaffolded)
packages/
  seo-rules/    Audit engine — rules, schemas, view-model derivations (Effect-TS, runtime-agnostic)
  ui/           Shared shadcn/ui components
  api/          API package
  env/          Environment config
  typescript-config/

seo-rules is runtime-agnostic so it can power non-extension surfaces (CLI, MCP server, desktop) later.

Stack

• TypeScript, Bun, Turborepo
• Effect-TS (rules engine, schemas, streams)
• WXT + React 19 (extension)
• Tailwind v4, shadcn/ui
• Vitest, Biome / Ultracite

Development

bun install
bun run dev           # all apps via turbo
bun run test          # NOT `bun test` — use `bun run test`
bun run typecheck
bun run lint

Extension-only:

cd apps/extension
bun run dev           # launches WXT dev build
bun run build
bun run zip           # packaged .zip for Chrome Web Store

Load the unpacked dev build from apps/extension/.output/chrome-mv3 in chrome://extensions.

Roadmap

1. Manual full-site audit — user-triggered sampled crawl with URL-pattern grouping, copyable site-wide report.
2. Additional interfaces — CLI, MCP server, desktop app sharing the same core.

Phase 2 targets Firefox; Edge and Safari later.

Documentation

• docs/plan/context.md — project context
• docs/plan/plan.md — roadmap
• docs/plan/plan-extension.md — shipped extension plan
• docs/plan/user-stories.md
• docs/plan/json-ld-improvements.md