Visa’s Trusted Agent Protocol (TAP) is a way for an AI shopping agent to prove to a merchant’s website who it is and what it wants to do, using a cryptographic signature on each web request. Visa introduced it with Cloudflare on October 14, 2025. A year later it is no longer only a specification: Visa says TAP and its Agentic Directory let merchants in Europe accept live agent-made purchases from July 2026, and a business-payments pilot with BILL and Billtrust went live in October 2026.
Last checked November 10, 2026, against Visa’s newsroom, the Visa Developer Center and Visa’s public GitHub repository.
What TAP does
According to Visa’s announcement, an agent presents signed information covering three things:
- Agent intent: that it is a trusted agent that wants to read product details or buy a specific product.
- Consumer recognition: whether the shopper already has an account with the merchant or has dealt with it before.
- Payment information: optionally, payment data for the merchant’s preferred checkout method.
The aim is to let a merchant welcome a legitimate shopping agent without treating every automated visit as a bot to block. Visa describes support for both guest checkout and logged-in customers.
How a merchant checks the signature
The Visa Developer Center puts the merchant’s job in one step: validate the message signature. The merchant’s system rebuilds the signature base string from attributes of the incoming request and checks it against the agent’s public key. If it verifies, the request came from that agent and was not altered.
The signature follows RFC 9421, the IETF standard for HTTP Message Signatures. In Visa’s sample implementation on GitHub, the signed components include the site (@authority), the page (@path), creation and expiry times, a nonce and a key identifier. That binds each signature to one merchant, one page and a short time window, which is how the protocol guards against a captured request being replayed elsewhere. The sample uses a tag of agent-browser-auth for browsing product details and agent-payer-auth for checkout, and supports Ed25519 and RSA-PSS-SHA256 keys.
A valid signature proves identity and intent. It does not approve the payment. The cardholder’s bank still authenticates and authorizes the transaction; in Visa’s European live transactions, that was done with Visa Payment Passkeys.
What happened after the launch
Every row below comes from a Visa press release or Visa’s own repository.
| Date | What Visa announced or published |
|---|---|
| October 14, 2025 | TAP released with Cloudflare, in the Visa Developer Center and on GitHub. Initial specifications apply to the Visa network. |
| October 28, 2025 | Nonce-validation sample code added to the GitHub repository, its latest commit as of November 10, 2026. |
| December 18, 2025 | Akamai joins as a TAP supporter, integrating it with its bot and abuse protection. |
| April 8, 2026 | Intelligent Commerce Connect, in pilot, lets merchants accept payments started through TAP and other agent protocols in one integration. |
| June 10, 2026 | Visa describes its Agentic Directory of agents and merchants it has verified. |
| July 2, 2026 | Live agent purchases in Europe with more than 30 issuers and merchants including lastminute.com, Frasers, Cleverbridge and BrickDepot; merchant participation runs on TAP and the directory, with Cloudflare and Akamai supporting implementation. |
| October 21, 2026 | BILL and Billtrust pilot uses TAP and Visa Intelligent Commerce for agents paying approved invoices through supplier portals. |
Two limits stay in place. The first public specification is written for the Visa network, and Visa says it is working with the IETF, the OpenID Foundation and EMVCo rather than claiming a finished standard. And the merchants named so far are participants in Visa programs, not evidence that every Visa merchant accepts agent purchases.
Where it sits among other agent protocols
At launch Visa said TAP would complement the Agentic Commerce Protocol and that it was working with Coinbase on interoperability with x402. These pieces answer different questions: TAP tells the merchant which agent is at the door, while protocols such as Google’s AP2 record what the customer authorized and UCP describes the checkout workflow. Visa’s April 2026 release lists TAP, the Machine Payments Protocol, ACP and UCP as protocols Intelligent Commerce Connect can accept.
