Google has announced the launch of the Agent Payments Protocol (AP2), a new open standard designed to securely enable AI agent-led payments across digital platforms.
Developed in collaboration with over 60 global partners including Coinbase, Mastercard, PayPal, American Express, Adyen, and UnionPay International, the initiative seeks to establish the foundational rules for a fast-emerging era of autonomous commerce.
AP2 builds on Google’s existing Agent2Agent (A2A) and Model Context Protocol (MCP) frameworks, extending them into the payments ecosystem. The company said the protocol introduces a payment-agnostic system, allowing users, merchants, and financial institutions to transact seamlessly across multiple payment methods, from credit cards and bank transfers to stablecoins and cryptocurrencies.
“AI agents are capable of transacting on behalf of users, which creates a need to establish a common foundation to securely authenticate, validate, and convey an agent’s authority to transact,” Google explained.
Addressing a new payments challenge
Unlike traditional digital transactions, which assume that a human is actively clicking “buy,” AI agents can now initiate purchases independently. This shift, Google noted, raises critical questions of authorisation, authenticity, and accountability—issues AP2 is designed to resolve.
To achieve this, the protocol uses Mandates—tamper-proof, cryptographically signed digital contracts that confirm a user’s intent. These mandates, verified by digital credentials, form a traceable audit trail from shopping cart to payment confirmation, ensuring that every transaction is both secure and non-repudiable.
AP2 also supports two key modes of shopping: real-time purchases, where the user is present, and delegated tasks, where an agent completes transactions on the user’s behalf.
As part of its commitment to decentralised finance, Google has worked with Coinbase, Ethereum Foundation, and MetaMask to create the A2A x402 extension, which brings crypto-native payments into the AP2 ecosystem. The x402 extension enables agent-to-agent stablecoin transactions, a move industry leaders say could accelerate adoption of Web3 payment models.
“x402 and AP2 show that agent-to-agent payments aren’t just an experiment anymore, they’re becoming part of how developers actually build,” said Erik Reppel, head of engineering, Coinbase Developer Platform. “It’s exciting to see agents paying each other resonate with the broader AI community.”
Pablo Fourez, chief digital officer at Mastercard, said the company’s collaboration with Google and other partners is part of its broader work with standards bodies such as the FIDO Alliance, aimed at embedding trust and security into next-generation payments.
Google envisions AP2 not only as a tool for consumer transactions but also as a foundation for enterprise use cases, such as autonomous procurement, subscription scaling, and AI-managed B2B purchases via Google Cloud Marketplace.
“AP2 is an open, shared protocol that prevents a fragmented ecosystem while offering a consistent, secure experience for users, merchants, and institutions,” the company said, while also adding “It creates the building blocks for AI-driven commerce and sets the stage for new commercial models.”
By establishing AP2 as a universal standard, Google hopes to bring together networks, issuers, merchants, and developers to collaborate on the future of payments. The company emphasised that the protocol will evolve through an open, industry-wide process, ensuring global scalability as AI continues to reshape digital transactions.