Payment Gateway Integration Skill for Claude
Integrates payment processing with Stripe, PayPal, or Square including subscriptions, webhooks, and PCI compliance. Use when implementing checkout flows, recurring billing, or handling refunds and disputes.
Install
one command, takes just this skill from the repositorynpx skills add https://github.com/secondsky/claude-skills --skill payment-gateway-integrationThe instruction itself
6 sections, as written by the authorPayment Gateway Integration
Integrate secure payment processing with proper error handling and compliance.
Stripe Integration (Node.js)
const stripe = require('stripe')(process.env.STRIPE_SECRET_KEY);
class PaymentService {
async createPaymentIntent(amount, currency, customerId) {
return stripe.paymentIntents.create({
amount: Math.round(amount * 100), // Convert to cents
currency,
customer: customerId,
automatic_payment_methods: { enabled: true }
});
}
async createSubscription(customerId, priceId) {
return stripe.subscriptions.create({
customer: customerId,
items: [{ price: priceId }],
payment_behavior: 'default_incomplete',
expand: ['latest_invoice.payment_intent']
});
}
async refund(paymentIntentId, amount = null) {
const params = { payment_intent: paymentIntentId };
if (amount) params.amount = Math.round(amount * 100);
return stripe.refunds.create(params);
}
}
Webhook Handling
app.post('/webhooks/stripe', express.raw({ type: 'application/json' }), (req, res) => {
const sig = req.headers['stripe-signature'];
let event;
try {
event = stripe.webhooks.constructEvent(req.body, sig, process.env.STRIPE_WEBHOOK_SECRET);
} catch (err) {
return res.status(400).send(`Webhook Error: ${err.message}`);
}
switch (event.type) {
case 'payment_intent.succeeded':
await handlePaymentSuccess(event.data.object);
break;
case 'invoice.payment_failed':
await handlePaymentFailed(event.data.object);
break;
}
res.json({ received: true });
});
PayPal Integration
See references/paypal-integration.md for complete PayPal implementation with:
- Order creation and capture
- Refund processing
- Webhook handling
- Frontend SDK integration
- Success/cancel callbacks
Security Checklist
- [ ] Use official SDK only
- [ ] Verify webhook signatures
- [ ] Never log full card numbers
- [ ] Store minimal payment data
- [ ] Test in sandbox first
- [ ] HTTPS for all payment routes
- [ ] Handle all error cases
- [ ] Use idempotency keys
- [ ] Implement retry logic
Best Practices
Do:
- Use official SDK libraries
- Verify all webhook signatures
- Log transaction IDs (not card data)
- Test in sandbox environment
- Handle all payment states
- Implement proper error messages
Don't:
- Process raw card data directly
- Store sensitive payment info
- Hardcode API keys
- Skip webhook signature validation
- Ignore failed payment events
- Use test keys in production
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How to use it
Take secondsky/payment-gateway-integration from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.