AP2 as an A2A Extension

Before writing code

Fetch live docs:

1. Fetch https://ap2-protocol.org/specification/ for the A2A extension specification
2. Fetch https://ap2-protocol.org/topics/ap2-a2a-and-mcp/ for protocol integration details
3. Web-search site:github.com google-agentic-commerce AP2 a2a extension for reference implementation
4. Web-search site:github.com google-agentic-commerce AP2 samples a2a for A2A-based samples

Conceptual Architecture

AP2 Extends A2A

AP2 is designed as a direct extension of the A2A protocol. It adds payment-specific capabilities to A2A's general-purpose agent-to-agent communication:

• A2A provides: tasks, messages, parts, streaming, agent cards
• AP2 adds: mandates, payment flows, VDCs, cryptographic signing, risk signals