Developer’s Guide to AI Agent Protocols

Source: Google Developers Blog

Overview

This blog post introduces a suite of six protocols, such as MCP and A2A, designed to eliminate custom integration code by standardizing how AI agents access data and communicate.

Protocol Suite

The protocols provide a common framework for AI agents, covering areas like data access, communication, and transaction handling. Notable protocols in the suite include:

• MCP
• A2A
• UCP (used for wholesale commerce)
• AP2 (used for secure payment authorization)

Kitchen Manager Example

A practical “kitchen manager” agent demonstrates how these tools handle complex tasks:

• Real‑time inventory checks
• Wholesale commerce via UCP
• Secure payment authorization through AP2

Agent Development Kit (ADK)

By leveraging the Agent Development Kit (ADK), developers can also implement:

• A2UI – for interactive dashboards
• AG-UI – for seamless streaming interfaces to users