Payments & Settlement
how agents authorize and move value
7 of 28 The Agent Protocol Atlas
- x402 Revives the dormant HTTP 402 status code so an agent can pay for a resource inline — request, get 402 with terms, pay in stablecoin, retry.
- AP2 Payment-agnostic settlement inside the A2A task lifecycle — handles cards, bank transfers and crypto through one mandate-based framework.
- ACP (Agentic Commerce) Lets an agent complete a purchase inside the conversation — the checkout that powers ChatGPT's Instant Checkout.
- UCP An open standard for interoperability between commerce entities so AI agents can discover products, fill carts, and complete purchases — orchestrating A2A, AP2 and MCP across the commerce journey.
- MPP Stripe and Tempo's open standard for billing AI agents over HTTP — agents discover prices, pay, subscribe and reconcile across stablecoins, cards and BNPL, with cryptographic receipts.
- Kite A payments-and-identity layer for the agent economy: verifiable agent identities (Agent Passport), cryptographically enforced spending constraints, and stablecoin rails, integrating x402, AP2 and MCP.
- Visa TAP An open specification that signs an AI agent's identity into HTTP request headers so any merchant can cryptographically verify the agent is legitimate before agent-driven checkout.