STABLE402.COM

A reference implementation for the x402 payment protocol.
Working code. Documented patterns. Technical writing.
Built on Cloudflare's full stack — Astro, Pages, Workers, x402.

Demos

01 Live

Basic 402 Gate

A Worker returning a proper V2 x402 response. Accept USDC on Base Sepolia via Coinbase CDP. The canonical reference implementation.

View implementation →

02 Coming Soon

Rate-Tiered Endpoint

Free tier returns a summary. The paid tier ($0.001/call, Bazaar-registered) returns the full structured dataset.

03 Coming Soon

Stripe Facilitator

The same x402 handshake, Stripe as facilitator. USDC on Base settles into your Stripe balance as fiat.

04 Coming Soon

MCP Server

An MCP server on Cloudflare Workers exposing a paid tool callable from Claude via the Payments MCP.

Writing

The x402 basic gate: a reference implementation on Cloudflare Workers 2026-03-12 · A complete walkthrough of the x402 V2 payment flow — request, 402 response, PAYMENT-REQUIRED header, facilitator verification, and settlement — deployed as a live endpoint at api.stable402.com/gate.