AP2 technical specification · Mandate · Payment Intent · Settlement Adapter

Wiki route

This entry sits under AI Agent payment protocols overview · a 7-protocol survey. Read it against AP2 · Google Agent Payments Protocol overview for peer / contrast context and payments index for the broader system / regulatory boundary.

Key facts

• The Authorization Mandate uses the W3C Verifiable Credential format ^•
• Items included in the mandate scope: amount, merchant category, time window (typically 24h), and an optional address restriction ^•
• Wallet Adapter abstraction layer: the same mandate can route to Google Pay (card) or USDC (via Coinbase Onchain Kit) ^•
• The Risk Score is computed by Google fraud detection AI, with merchants customizing the threshold ^•
• The audit trail is written back to the user’s Google account, verifiable by multiple parties — user/merchant/regulator ^•

Mechanism / How it works

Typical flow (5 steps):

1. The user tells Gemini “book me a flight next Sunday, budget $800”
2. Gemini issues an Authorization Mandate (scope: airline category / limit: $800 / expire: 24h)
3. Gemini calls the airline API and submits a Payment Intent (referencing the mandate)
4. The airline verifies the mandate + settles via the AP2 settlement adapter (Google Pay or USDC)
5. The audit trail is written back to the user’s Google account

The Wallet Adapter is AP2 ’s key abstraction — neither the mandate nor the intent is bound to a concrete settlement rail, and the merchant only needs to integrate 1 AP2 API(s) to simultaneously accept card payments and stablecoin payments (see USD Stablecoin Interchange Market). This differs in route from the x402 protocol (explicitly USDC-first): AP2 is “rail-neutral” · x402 is “USDC-native”. Cross-chain USDC settlement requires coordination between CCTP V2 and chain abstraction.

Origin & evolution

The W3C Verifiable Credentials standard itself has been advanced continuously by the W3C since 2019 , with Google as a core contributor. AP2 ’s spec design directly borrows the VC model as the mandate container, inventing no new authorization object — this lowers the integration cost with the existing identity/DID ecosystem (Microsoft Entra Verified ID, Decentralized Identity Foundation, etc.).

2025-09 draft → 2026-Q1 v1.0; during this period the main adjustments concentrated on the settlement adapter interface and the risk score schema.

Related

• Wiki Index
• AP2 Overview
• AP2 Adoption
• CCTP V2 overview · Circle USDC cross-chain burn-and-mint

Sources

• W3C Verifiable Credentials Data Model
• Google AP2 spec v1.0
• Google AP2 (Agent Payments Protocol) — https://github.com/google-agentic-commerce/AP2