Public Goods

// 1. Discover Public Goods's UCP manifest and capabilities
const resp = await fetch('https://publicgoods.com/.well-known/ucp');
const { ucp } = await resp.json();

// 2. Connect via MCP transport for product browsing
const mcpEndpoint = ucp.services['dev.ucp.shopping']
  .find(s => s.transport === 'mcp')?.endpoint;
// → "http://publicgoods.com/api/ucp/mcp"

// 3. Initialize an MCP client session
import { Client } from '@modelcontextprotocol/sdk/client/index.js';
import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js';

const client = new Client({ name: 'shopping-agent', version: '1.0.0' });
await client.connect(new StreamableHTTPClientTransport(
  new URL(mcpEndpoint)
));

// 4. Browse products via MCP tools
const products = await client.callTool({
  name: 'search_products',
  arguments: { query: 'bestsellers', limit: 10 }
});

// 5. Initiate checkout (requires UCP identity token)
const checkout = await client.callTool({
  name: 'create_checkout',
  arguments: {
    items: [{ product_id: 'PRODUCT_ID', quantity: 1 }],
    identity_token: consumerToken
  }
});

// Supports: checkout, fulfillment tracking, discount codes
// Accepts: Google Pay (Visa, MC, Amex, Discover) + Shopify Card