MPP

beta

Machine Payments Protocol (MPP)

by Stripe, Tempo· launched 2026-03verified 2026-09-03

At a glance

Layer
execution
Category
hybrid
Rails
cards, stablecoins, USDC
Settlement
Settles through Stripe (PaymentIntents), across card and stablecoin rails; stablecoin settlement via the Tempo blockchain.
Reversible
Yes
Human in loop
optional
D2C fit
moderate
B2B fit
strong
Spec
https://mpp.dev

An open, internet-native protocol for machine and agent payments, co-authored by Stripe and Tempo. Spans both card (via Shared Payment Tokens) and stablecoin rails, settling through Stripe's existing infrastructure. The spec is open at mpp.dev; Stripe acceptance is in early access as of September 2026.

How it works

MPP is an open standard co-authored by Stripe and Tempo that lets agents pay for APIs and services programmatically without a checkout UI.

  • 402 challenge flow. When an agent requests a resource, the service returns an HTTP 402 response with payment details. The agent authorizes the payment, retries the request, and receives the resource with a receipt.
  • Rail coverage. MPP spans card and stablecoin rails. Cards are handled via Shared Payment Tokens (SPTs) — scoped grants that let an agent use a customer's payment method with usage and expiration limits. Stablecoin payments settle via the Tempo blockchain. Stripe's machine-payments surface also supports x402 for stablecoin-only flows.
  • Payment shapes. Covers one-shot, recurring, and streaming payments, so an agent can pay once or maintain ongoing/metered obligations.
  • Settlement. Flows settle through Stripe PaymentIntents, which means agent payments reuse Stripe's reconciliation, reporting, and (for card rails) dispute handling.

The specification is open at mpp.dev. Stripe acceptance remains in early access; dynamic pricing for MPP is on Stripe's public preview roadmap. This entry is marked beta accordingly.

Tradeoffs

  • Reversibility is mixed: card-rail payments retain dispute/refund rights, but stablecoin settlement does not — a single 'reversible' flag over-simplifies, so confirm per rail.
  • Settling through Stripe implies operating within Stripe's account, availability, and compliance model rather than a permissionless one.
  • As an early-access surface, capabilities and interfaces may shift; integrations should track Stripe's changelog.

Security & limitations

  • Agent-initiated recurring/streaming payments require robust scoping and revocation to prevent runaway or manipulated charges.
  • Where MPP bridges to stablecoin/x402 flows, the non-reversibility and custody considerations of on-chain settlement apply to that leg.
  • Shared Payment Tokens carry scoped card access; token leakage or insufficient scope constraints could enable unauthorized charges.

See sources below. Documented for commentary and identification only.

Fits together with

  • x402 — x402 Payment Protocol

Deployments using MPP

  • Stripe Machine Payments

    Stripe

    B2Blive

    Stripe's production machine-payments surface: accepts agent payments via MPP (card + stablecoin, one-shot through recurring/streaming) and also supports x402 for stablecoin-only flows, settling through Stripe PaymentIntents.

    Chains
    Tempo, Base
    Launched
    2026-03
    verified 2026-09-02source

Sources

  1. [1]Machine payments — Overview— Stripe
  2. [2]MPP payments — Machine Payments Protocol— Stripe
  3. [3]Introducing the Machine Payments Protocol— Stripe, 2026-03
  4. [4]MPP specification— MPP (Stripe & Tempo)