Introducing x402-mcp: Open protocol payments for MCP tools

Vercel introduced x402-mcp, an open protocol that integrates payments into HTTP requests using the 402 Payment Required status code, enabling programmatic payments for MCP servers and the Vercel AI SDK without prior account setup.

The protocol is payment-network agnostic and currently settles as exact, one-time payments in USDC on the Base blockchain.

Vercel also released an x402 AI Starter template demonstrating the protocol with Next.js, AI SDK, AI Elements, and AI Gateway.