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Romain Loupias
Romain Loupias

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I built a Chrome extension that reads SaaS Terms of Service so you don't have to

Every SaaS has a Terms of Service. Nobody reads it.

I got burned by an auto-renewal clause I missed. Paid for a full year of a tool I'd stopped using 3 months in. When I went back to read the ToS, the clause was in paragraph 14, written in legal language that would take a lawyer to parse.

So I built Explain Legal, a Chrome extension that does it automatically.

How it works

When you land on a SaaS pricing page, the extension:

  1. Detects that you're on a pricing or checkout page
  2. Silently fetches the Terms of Service from the same domain
  3. Analyzes it with Claude (Anthropic's API)
  4. Surfaces the results in a sidebar — no clicking required

What it shows you

  • A verdict: Safe, Caution, or Avoid
  • Up to 3 red flags focused on financial risk (auto-renewal, non-refundable payments, price change rights)
  • 2 questions to ask support before you commit

The technical stack

  • Chrome Extension (Manifest V3, vanilla JS)
  • Vercel serverless function as a proxy (keeps the API key server-side)
  • Upstash Redis for usage tracking (freemium model — 3 free scans)
  • Claude API for the analysis
  • Stripe for payments

The interesting engineering problem

The hardest part wasn't the AI analysis, it was reliably finding and fetching the ToS page from any domain. Some sites link to /terms, others to /legal/terms-of-service, others bury it in the footer with non-standard anchor text.

The current approach: scan for anchor tags containing "terms", "tos", "legal", or "conditions" on the same domain, with a fallback to /terms. Works for ~85% of sites.

Try it

It's live on the Chrome Store: Explain Legal

3 free scans included.

Happy to answer questions about the build.

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