On Tuesday, Google announced a new open protocol for purchases initiated by AI agents. These automated software programs can shop and make decisions on behalf of users. The announcement came with backing from more than 60 merchants and financial institutions.
Called the Agent Payments Protocol, or AP2, the system is designed to be interoperable between AI platforms, payment systems, and vendors. It provides a traceable paper trail for every transaction.
In a post announcing the protocol, Google executives emphasized their commitment to openness. They stated the company is committed to evolving the protocol through an open, collaborative process, including through standards bodies. They invited the entire payments and technology community to help build this future. The full specification for AP2 was posted to GitHub alongside the announcement.
The protocol is built for a future where AI agents routinely shop for products on a customer’s behalf and engage in complex real-time interactions with retailers’ own AI agents. One example from Google imagines a user asking their agent to shop for a bike trip. This request could trigger a spontaneous, time-sensitive bundle offer from a bike shop’s agent.
Another example describes a user requesting travel and lodging for a weekend vacation by providing only the dates, location, and budget. The agent can then interact with airline and hotel agents, as well as online travel agencies and booking platforms. Once it finds a combination that fits the budget, it can execute both cryptographically-signed bookings simultaneously.
Enabling this kind of transaction is complex from both a technological and social standpoint. AP2 requires agents to register two separate approvals before a purchase is finalized. The first is an “intent mandate,” which is essentially a user telling the AI what they are looking for. This enables the agent to search for a specific item and negotiate with sellers. The second is a “cart mandate,” which gives final approval for a purchase once a specific item has been found.
The protocol also contains a provision for fully automated purchases. In this scenario, the agent is permitted to automatically generate a cart mandate once an item is found. These circumstances require a more detailed intent mandate that specifies price limits, timing, and other rules of engagement. In either case, the goal is to maintain an auditable trail that can be re-examined in cases of fraud.
In collaboration with cryptocurrency outfits Coinbase, Metamask, and the Ethereum Foundation, Google also produced an extension to integrate the cryptocurrency-oriented x402 protocol. This allows for AI-driven purchasing directly from crypto wallets.
A number of other tech companies are working on their own agentic purchasing systems. Perplexity notably allows for a Buy With Pro service in its agentic browser. The payment provider Stripe also produces software tools for agentic purchasing on its platform, though they are not as comprehensive as AP2.
Like any protocol, the impact of AP2 will depend on its support from other players in the ecosystem, particularly developers building agentic purchasing systems. However, AP2 has already won the support of major financial providers like Mastercard, American Express, and PayPal, giving the protocol a significant immediate footprint.