What is the difference between x402, AMP, and MPP?

x402 is pay-per-request (one on-chain transaction per API call). AMP uses persistent payment channels (one on-chain transaction covers thousands of calls). MPP supports both per-request and session modes with fiat payment support via Stripe.

Which AI agent payment protocol should I use?

Use x402 for simple, low-volume API access. Use AMP for high-frequency agent workflows (100+ calls per session). Use MPP if you need fiat payment support alongside crypto.

AI Payments

x402 vs AMP vs MPP: Choosing the Right Payment Protocol for AI Agents

March 27, 2026

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8 min read

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Aggelos Kappos(Founder @ QBT Labs)

x402AMPMPPAI AgentsMachine PaymentsPayment ProtocolsCrypto

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