Machine Payments Protocol Standardizes Agent Commerce

MPP is an open protocol built around HTTP 402 that lets AI agents handle payments autonomously - stablecoins, Bitcoin Lightning, Stripe, and card transactions all work through the same standardized flow. SDKs ship in Python, Rust, and TypeScript with framework support for Express, Next.js, and Hono. The protocol supports one-time charges, pay-as-you-go sessions, and streamed per-token billing via Server-Sent Events, and it integrates with MCP for model-native payment handling. The timing is right: as agents start operating across APIs and services without human intervention, the missing piece has been a machine-readable way to pay for things. Stripe, Visa, and several crypto infrastructure teams have been circling this same problem from different angles, but MPP is the first attempt to define it as a protocol rather than a product.