Understanding x402 and MPP: Two Approaches to Agent Payments
Stripe's MPP and x402 represent two competing approaches to enabling machine-to-machine payments, both leveraging the long-dormant HTTP 402 status code ("Payment Required").
x402, led by Coinbase, is a minimalist protocol that embeds payment directly into HTTP requests. It requires no accounts, API keys, or intermediaries. A server returns a 402 response with payment details; the client pays on-chain and resubmits the request with a proof. It's open-source, chain-agnostic (currently supporting Base, Polygon, Solana), and designed for open, permissionless systems. However, current usage is low, with small microtransactions.
MPP, developed by Stripe and Tempo, is a full-stack solution built for high-frequency agent transactions. Its core innovation is sessions, allowing an agent to pre-authorize a spending limit and make numerous micro-payments within it without repeated on-chain transactions. It runs on the Tempo blockchain, optimized for high throughput and sub-second confirmations. Crucially, it integrates with Stripe's existing compliance, risk, and fiat infrastructure, including support for credit cards via Shared Payment Tokens (SPTs).
While x402 offers simplicity and decentralization, MPP provides scalability and enterprise-grade features. Stripe supports both, aiming to capture agent payment flows regardless of the underlying protocol. The ecosystem is still experimental, but major players like Google, Visa, and Anthropic are involved. The choice depends on the use case: x402 for open, long-tail applications, and MPP for commercial, high-volume scenarios.
marsbit03/22 03:30
