Complete TypeScript Server SDK for MCP Tool Monetization

[ryanRfox]

Summary

Complete implementation of TypeScript Server SDK (@nanda/payments-sdk) focused on MCP developers who want to monetize their tools using NANDA Points.

Key Features:

• requirePayment(): Decorator to wrap free tools with payment requirements
• createPaidTool(): Create new payment-protected MCP tools
• quickSetup(): Rapid 3-line configuration for MCP servers
• paymentMiddleware(): Express middleware for route-level payment protection

Phase 1 Completed:

• ✅ Complete TypeScript Server SDK implementation
• ✅ MCP-specific payment wrapper utilities extracted from working packages/shared
• ✅ x402-compliant payment middleware following Coinbase patterns
• ✅ Zero TypeScript compilation errors with full type safety
• ✅ Working MCP server examples demonstrating tool monetization
• ✅ npm package ready for publication as @nanda/payments-sdk

Updated Documentation:

• PLAN.md: Phase 1 marked complete, Phase 2 (documentation) in progress
• PRD.md: Refocused on server-side MCP tool monetization use cases
• CLAUDE.md: Complete implementation architecture and usage patterns

Implementation Highlights

Quick Setup API

const payments = await quickSetup({
  facilitatorUrl: 'http://localhost:3001', 
  agentName: 'my-mcp-server'
});
const paidTool = payments.requirePayment({ amount: 50 })(freeTool);

Express Middleware

app.use(paymentMiddleware({
  '/api/premium': { amount: 25, description: 'Premium access' }
}, config));

MCP Tool Creation

const weatherTool = createPaidTool('premium_weather', 
  { amount: 100, description: 'Premium weather analysis' },
  config, async (args) => getPremiumWeatherData(args.location)
);

Test plan

• TypeScript compilation passes with zero errors
• All lint checks pass
• MCP server example builds and demonstrates paid tool functionality
• Facilitator integration works with existing endpoints
• Express middleware integrates with route-level payment protection
• Documentation updated to reflect server-side focus and completion status