We shipped webmcp-payments — agent payment acceptance for websites via x402

Something I kept running into building on u/mcp-b/global: agents can discover tools, invoke APIs, navigate forms — but they hit a wall the second a tool costs anything.

No standardized way for a website to say "this tool costs $0.02 per call, here's how to pay."

So we built webmcp-payments. Live on npm now: https://www.npmjs.com/package/webmcp-payments

PaymentGate middleware wraps any WebMCP tool with x402 payment enforcement. Agent hits tool, gets 402, pays on-chain, retries with proof, gets data. No billing dashboard needed.

Built on top of u/mcp-b/global — not replacing it. They handle agent sessions, we handle value exchange.

94 tests. TypeScript strict. Base chain + USDC.

First library doing website-side agent payment acceptance that we know of.