Tollstile vs MPP SDKs
What the Machine Payments Protocol SDK covers, and what Tollstile adds for merchants.
Public Beta · early access
MPP is payment-method agnostic: one protocol for stablecoins, cards through Stripe, and sessions. If MPP is the only protocol you will accept, its SDK covers the wire format — challenges, credentials, and receipts.
What Tollstile adds
- Merchant lifecycle across protocols: access policies, requirements, a ledger, and reconciliation that work the same for MPP, x402, and others.
- Correct timing per method: a Stripe charge captures when the PaymentIntent is confirmed, so Tollstile settles it before your handler and refunds when the handler fails; a Tempo charge is broadcast only after the handler succeeded; Tempo sessions (experimental) are reusable authorizations drawn down per call.
- Replay protection beyond the challenge HMAC, which does not prevent reuse by itself.
- Recovering timed-out charges by looking them up instead of failing the request or charging again.
Verification status
The MPP rails are implemented and tested against in-process fakes and mppx's published challenge vectors, not yet against Stripe or a Tempo node. The Tempo session rail is experimental. See MPP.