Stripe Not Working in Your AI-Built App? Step-by-Step Fix

Stripe is the payment system of choice for most AI-built apps. It has excellent documentation and SDKs for every language. But there are several ways AI tools implement Stripe incorrectly — and payment bugs are not just frustrating, they cost real revenue.

The Biggest Mistake: Secret Key in Frontend Code

The Stripe publishable key (pk_test_ or pk_live_) is safe to use in frontend code. The secret key (sk_test_ or sk_live_) must never be in frontend code. If your app has the secret key in a React component or any JavaScript that runs in the browser, anyone can use it to charge cards, issue refunds, and access your Stripe account. Fix this immediately before anything else.

The Correct Architecture

1) Frontend calls a Supabase Edge Function with the order details. 2) The Edge Function uses the Stripe secret key (stored as a Supabase secret) to create a PaymentIntent. 3) The Edge Function returns the client_secret to the frontend. 4) The frontend uses Stripe.js and the client_secret to complete the payment — without ever seeing the secret key.

Problem: Works in Test Mode, Fails in Production

Check two things: Are you using live keys (pk_live_ and sk_live_) instead of test keys? Did you fully activate your Stripe account — Stripe requires business details before processing live payments. Check Stripe Dashboard → Activations.

Problem: Webhooks Not Being Received

Common causes: the webhook URL is localhost (Stripe cannot reach this — use Stripe CLI for local testing), the webhook secret is wrong (causing signature verification failures), or your server returns a non-200 response. Fix: Stripe Dashboard → Webhooks → your endpoint → Recent deliveries to see exactly what Stripe sent and what your server returned.

Problem: Duplicate Orders

Webhooks can be delivered more than once. If your handler creates a record every time payment_intent.succeeded fires, you get duplicates. Fix: Before creating any record, check whether a record with that payment intent ID already exists. If so, return 200 without creating a duplicate.

Problem: User Paid but Account Was Not Activated

Never rely on the frontend redirect after payment to activate an account. Browser closes, network errors, and navigation away can prevent the redirect. Always use a webhook to activate accounts and fulfil orders — webhooks are reliable, redirects are not.

Test Your Full Payment Flow

Stripe provides test card numbers for every scenario. Use 4242 4242 4242 4242 for success, 4000 0000 0000 0002 for a declined card, and 4000 0027 6000 3184 for 3D Secure authentication. Test all three before going live.

If your Stripe integration is generating errors you cannot diagnose, share your Edge Function code and the Stripe Dashboard error logs with a developer. Stripe integration fixes are typically 3 to 5 hours of work.