Payment Processing

payment-processing

Integration patterns for Stripe, Polar, and Dodo payment systems. Handles checkout flows, webhooks, subscriptions, and billing. Use when: implementing payments, setting up subscriptions, handling webhooks.

Metadata

• Version: 1.0.0
• Category: api
• Source: workspace

Tags

payments, stripe, subscriptions, webhooks, billing, polar, dodo

MCP Dependencies

None specified

Inputs

• provider (string) (required): Provider: stripe, polar, dodo
• feature (string) (required): Feature: checkout, webhook, subscription, portal
• framework (string) (optional): Framework: nextjs, express, fastapi

Chain of Thought

1. Identify payment provider. 2. Select integration pattern. 3. Generate secure implementation. 4. Add webhook verification. 5. Include error handling. 6. Add testing guidance.

Workflow

No workflow defined

Anti-Hallucination Rules

None specified

Verification Checklist

None specified

Usage

// Execute via MCP Gateway:
gateway_execute_skill({ name: "payment-processing", inputs: { ... } })

// Or via REST API:
// POST /api/code/skills/payment-processing/execute
// Body: { "inputs": { ... } }

Code

// Payment Processing Skill
const provider = inputs.provider || 'stripe';
const feature = inputs.feature || 'checkout';

const integrations = {
  stripe: {
    checkout: `## Stripe Checkout (Next.js)

\`\`\`typescript
// app/api/checkout/route.ts
import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY!);

export async function POST(req: Request) {
  const { priceId } = await req.json();
  
  const session = await stripe.checkout.sessions.create({
    mode: 'subscription',
    payment_method_types: ['card'],
    line_items: [{ price: priceId, quantity: 1 }],
    success_url: \`\${process.env.NEXT_PUBLIC_URL}/success?session_id={CHECKOUT_SESSION_ID}\`,
    cancel_url: \`\${process.env.NEXT_PUBLIC_URL}/canceled\`,
  });
  
  return Response.json({ url: session.url });
}
\`\`\``,
    webhook: `## Stripe Webhook Handler

\`\`\`typescript
// app/api/webhook/route.ts
import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY!);

export async function POST(req: Request) {
  const body = await req.text();
  const sig = req.headers.get('stripe-signature')!;
  
  let event: Stripe.Event;
  try {
    event = stripe.webhooks.constructEvent(
      body, sig, process.env.STRIPE_WEBHOOK_SECRET!
    );
  } catch (err) {
    return new Response('Webhook Error', { status: 400 });
  }
  
  switch (event.type) {
    case 'checkout.session.completed':
      // Handle successful checkout
      break;
    case 'customer.subscription.updated':
      // Handle subscription changes
      break;
  }
  
  return new Response('OK');
}
\`\`\``
  },
  polar: {
    checkout: `## Polar.sh Integration

\`\`\`typescript
// Polar SDK setup
import { Polar } from '@polar-sh/sdk';

const polar = new Polar({ accessToken: process.env.POLAR_ACCESS_TOKEN });

// Create checkout
const checkout = await polar.checkouts.create({
  productId: 'prod_xxx',
  successUrl: 'https://yoursite.com/success',
});
\`\`\``,
    webhook: `## Polar Webhook

\`\`\`typescript
// Verify webhook signature
import { validateWebhookSignature } from '@polar-sh/sdk';

const isValid = validateWebhookSignature(
  payload, signature, process.env.POLAR_WEBHOOK_SECRET
);
\`\`\``
  }
};

const result = integrations[provider]?.[feature] || 'Provider/feature not found';
console.log(result);

Created: Tue Dec 23 2025 00:31:32 GMT+0800 (Singapore Standard Time) Updated: Tue Dec 23 2025 00:31:32 GMT+0800 (Singapore Standard Time)