AP2 Merchant Payment Processor Implementation

Before writing code

Fetch live docs:

1. Fetch https://ap2-protocol.org/ap2/specification/ for Payment Processor responsibilities
2. Web-search site:github.com google-agentic-commerce AP2 samples roles merchant_payment_processor for reference implementation
3. Web-search site:github.com google-agentic-commerce AP2 payment processor authorization for authorization flow
4. Fetch https://ap2-protocol.org/overview/ for MPP role details

Conceptual Architecture

What the Payment Processor Does

The Merchant Payment Processor (MPP) handles the financial side of the transaction on behalf of the merchant: