Tesla Price History — Chrome Extension

Adds a small badge to each car on tesla.com/*/inventory/used/{m3,my,ms,mx} showing how that exact VIN has been repriced over time, sourced from the TeslaPricing database.

Load locally (dev)

1. Open chrome://extensions
2. Turn on Developer mode (top-right)
3. Click Load unpacked and select this repo folder
4. Visit https://www.tesla.com/fr_FR/inventory/used/my — badges appear on each card

Click a badge for the full history popover.

Architecture

• content.js runs on used-inventory pages, fetches the current VIN list from Tesla's own inventory API (same origin, no auth), then calls our lookup-vins Supabase Edge Function to get price history.
• lookup-vins (Supabase Edge Function, deployed) validates VIN format, caps batch size at 50, returns the price history for each Tesla VIN we have on file.
• The anon JWT is bundled in content.js (publishable by design — same key used by the frontend). Abuse protection lives in the edge function: strict input validation + 5-minute response cache.

Files

• manifest.json — MV3, content-script only, zero permissions beyond matching tesla.com inventory URLs
• content.js — VIN extraction, lookup, badge injection, SPA-aware re-render
• overlay.css — badge + popover styling