How AI Agents Pay

When an AI agent buys something for you, four problems have to be solved at once: the payment credential has to reach the merchant without being exposed, the merchant has to know you actually authorized this purchase, the right party has to be on the hook if something goes wrong, and all of it has to happen without a human clicking “buy.” This page explains the mechanisms, then the specific products built on them.

The four mechanisms

Tokenization is the foundation. Instead of handing an agent a real card number, the networks and processors issue a token bound to a specific authorized agent and to the limits you set. Stripe’s Shared Payment Token is the processor-side version: a single-use credential scoped to one merchant and one cart total.

Mandates, or verifiable credentials, are the trust layer. This is the core of Google’s AP2: cryptographically signed, tamper-evident records of what you authorized, which a merchant or bank can verify and later use as dispute evidence.

Passkeys and delegated authority are how your approval is captured. Mastercard ties its agent tokens to payment passkeys and on-device biometrics; AP2 uses hardware-backed device keys; the Stripe and OpenAI model asks you to confirm each step explicitly. The common thread is strong, device-bound proof that the human, not just the agent, signed off.

Liability handling is the least settled of the four, and the products differ most here.

The network and processor products

Visa Intelligent Commerce opened Visa’s network to AI agents, announced on 30 April 2025. It centers on “AI-Ready Cards,” which replace card details with tokenized credentials that confirm a chosen agent is authorized to act for the consumer, with spending limits and conditions the consumer sets. Launch collaborators named by Visa included Anthropic, IBM, Microsoft, Mistral AI, OpenAI, Perplexity, Samsung, and Stripe. By a December 2025 update, Visa described hundreds of agent-initiated transactions and a growing partner roster, but the program was still in closed beta and pilot, not general availability. On 8 April 2026 Visa added Intelligent Commerce Connect, a network, protocol, and token-vault-agnostic “on ramp” that lets merchants accept agent-initiated payments through a single Visa Acceptance Platform integration, working across major agent protocols including the Trusted Agent Protocol, the Machine Payments Protocol, ACP, and UCP. Visa launched it in pilot with partners including AWS and Highnote, with broader rollout continuing through 2026; Visa’s own announcement said only that it would reach more partners during the year, while trade reporting put general availability around the end of June 2026. Visa also led a separate effort, the Trusted Agent Protocol, to help merchants tell legitimate agents from bots.

Mastercard Agent Pay was announced a day earlier, on 29 April 2025. It uses Mastercard Agentic Tokens, built on the same tokenization behind contactless and Mastercard Payment Passkeys, and requires agents to be registered and verified before they can pay, with consumers setting controls over what an agent may buy. Named partners included Microsoft, IBM, Braintree, and Checkout.com.

American Express entered later, on 14 April 2026, with two things together: an Agentic Commerce Experiences developer kit and Amex Agent Purchase Protection, an explicit commitment to back card-member purchases made by registered agents. That consumer-protection pledge is the most concrete liability stance any network has made. The developer kit went to select partners first, so this is early-stage rather than broadly available.

PayPal plays a dual role: it is an AP2 launch partner, announced on 16 September 2025, and it offers an agent toolkit and remote MCP server so businesses can build agentic experiences on PayPal’s APIs. Its AP2 work maps the protocol’s mandates, expressed as W3C verifiable credentials, onto PayPal’s wallet, checkout, and dispute workflows, though much of it is framed as architecture and intent rather than shipped features.

Stripe co-developed the Agentic Commerce Protocol with OpenAI and powers Instant Checkout in ChatGPT, which is the single most concretely live consumer-facing agentic payment flow in this list. Its mechanism is the Shared Payment Token described above, launched on 29 September 2025 for US buyers.

Stablecoins and the machine-to-machine rail

For payments between software rather than consumer checkout, the leading approach is x402, an open protocol from Coinbase that revives the dormant HTTP “402 Payment Required” status code to let software settle in stablecoins such as USDC directly over the web, with no accounts or card credentials. A buyer requests a resource, the server responds with payment instructions, the buyer returns a signed payment, and a facilitator verifies and settles the transaction on-chain. In September 2025, Coinbase and Cloudflare announced an x402 Foundation to steward it as a neutral standard, and Google aligned it with AP2 through the A2A x402 extension. This is live infrastructure, but it is aimed at agent-to-agent and micro-transaction use cases, not retail checkout.

A second machine-native standard arrived in March 2026: the Machine Payments Protocol (MPP), an open protocol co-authored by Stripe and Tempo for agents to pay services programmatically, for things like microtransactions, recurring payments, and paying per API call. An agent requests a resource from a service, API, or MCP endpoint, the service returns a payment request, the agent authorizes it, and the resource is delivered. Stripe lets businesses accept MPP payments through its existing PaymentIntents API, in stablecoins as well as cards and buy-now-pay-later via Shared Payment Tokens, so the funds settle into a normal Stripe balance. Like x402, MPP targets the software-to-software lane rather than consumer retail checkout, and Stripe supports both.

Announced versus live

The honest summary is that there is far more announced than live. The genuinely live consumer flow is Stripe and OpenAI’s Instant Checkout, and even that started US-only and limited. Visa’s and Mastercard’s programs are pilots and closed betas. American Express’s developer kit reached select partners in April 2026. Across the industry, there have arguably been about as many announcements as real transactions. x402 and MPP are real and running, but in a different lane.

Liability deserves a final word because it is what merchants and consumers will care about most. Only American Express has made a concrete consumer-protection pledge. AP2’s design places accountability on humans, merchants, and issuers rather than the agent. But no finalized, cross-network rulebook for disputing an agent-initiated purchase exists yet, and that gap, more than any technical one, is what still has to close.

FAQ

What is actually live versus announced? The clearest live consumer flow is Stripe and OpenAI’s Instant Checkout. Visa and Mastercard are in pilot or closed beta (Visa’s Intelligent Commerce Connect on-ramp is rolling out through 2026, with trade reporting pointing to general availability around the end of June 2026); American Express shipped a developer kit to select partners in April 2026; x402 and MPP are live but for machine-to-machine payments.

How does an agent pay without exposing my card number? Tokenization. The real card number is replaced by a token bound to a specific authorized agent and your limits; Stripe’s Shared Payment Token is single-use and scoped to one merchant and cart total.

Who is liable if an agent buys the wrong thing? Rules are not settled. Amex has pledged protection for purchases by registered agents; AP2 puts accountability on humans, merchants, and issuers; no cross-network chargeback rulebook exists yet.