# Visa Trusted Agent Protocol (TAP)

> A cryptographic trust framework for agentic commerce on the Visa network. Uses RFC 9421 HTTP Message Signatures so a Visa-approved AI agent can prove its identity, consumer authorization, and payment credentials to merchants — letting merchants distinguish legitimate buying agents from bots. Live in Europe with 30+ issuers since July 2026.

## At a glance

| Field | Value |
| --- | --- |
| Name | TAP |
| Layer | payment-authorization |
| Category | card-rail |
| Status | live |
| Created by | Visa, Cloudflare |
| Launched | 2025-10 |
| Rails | cards |
| Settlement | Delegates settlement to Visa's existing card network; TAP governs agent identity verification and authorization. |
| Reversible | — |
| Human in loop | optional |
| D2C fit | strong |
| B2B fit | moderate |
| Spec | https://developer.visa.com/capabilities/trusted-agent-protocol/docs |
| Last verified | 2026-09-14 |

## How it works

TAP addresses a specific merchant-side problem: **how does a website know the automated visitor at checkout is a legitimate agent, not a scraper or carding bot?**

- **Cryptographic signatures.** A Visa-approved agent signs every HTTP request with a private key using **RFC 9421 HTTP Message Signatures** (Ed25519 or RSA-PSS-SHA256). The signature covers timestamps, a nonce, a key identifier, and a tag indicating the action (browsing or payment), so the merchant can verify that the request is current and not replayed.
- **Three-signature model.** TAP defines three layered signatures: (1) **Agent Intent** — proves the agent is registered and has a commerce purpose; (2) **Consumer Recognition** — passes verifiable consumer identifiers so the merchant can recognise returning customers; (3) **Payment Information** — carries Payment Account References (PARs) or other credentials to streamline checkout.
- **Agent Directory.** Merchants verify agent public keys against Visa's Agent Directory. Cloudflare and Akamai embed TAP verification into their edge networks, so merchants behind those CDNs can adopt TAP with no new infrastructure.
- **Issuer authentication.** On the issuer side, Visa Payment Passkeys authenticate agent-initiated transactions and support European Strong Customer Authentication (SCA) requirements.

TAP is deliberately **not a settlement rail** — it layers trust and identity on top of Visa's existing card network. It complements execution protocols like x402 by solving the "who is this agent?" question that x402's HTTP 402 flow does not address.

## Tradeoffs

- Tied to the Visa network: merchants and agents must operate within Visa's credentialing and directory ecosystem.
- Requires agent registration with Visa, which creates a centralised trust anchor rather than a permissionless identity model.
- Adoption depends on CDN and acquirer integration; merchants not behind Cloudflare or Akamai need custom implementation.
- The protocol governs identity and authorization only — settlement, pricing, and dispute handling remain on Visa's existing card rails.

## Security & limitations

- Security rests on the integrity of the agent's private key and Visa's Agent Directory; compromise of either undermines the trust chain.
- The three-signature model binds agent identity to consumer credentials and payment data via a shared nonce — a nonce mismatch invalidates the binding even if individual signatures verify.
- As with any centralised directory model, the Agent Directory is a single point of failure for trust verification.

## Fits together with

- x402

## Sources

1. [Visa Introduces Trusted Agent Protocol: An Ecosystem-Led Framework for AI Commerce](https://usa.visa.com/about-visa/newsroom/press-releases.releaseId.21716.html) — Visa, 2025-10-14
2. [Getting Started with Visa's Trusted Agent Protocol](https://developer.visa.com/capabilities/trusted-agent-protocol/docs) — Visa Developer Center
3. [Visa Trusted Agent Protocol — reference implementation and samples](https://github.com/visa/trusted-agent-protocol) — Visa (GitHub)
4. [Visa and Banks Across Europe Reach the Next Phase of Agentic Commerce](https://www.visa.co.uk/about-visa/newsroom/press-releases.3457328.html) — Visa, 2026-07-02

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_Source: payful.ai — independent editorial reference. Verified 2026-09-14._