[Advent of Agents] Day 21: Developer's Guide to AI Agent Protocols

[abraha...@google.com]

Hi everyone,

Day 21 of Google's Advent of Agents — Season 2 is now live! 🌸

Stop guessing which agent protocol to use and start building with this definitive guide to the emerging industry standards. Learn how to incrementally layer protocols like MCP and A2A to transform a simple chatbot into a production-ready supply chain agent.

Today's Highlights:

• A clear breakdown of the six essential protocols (MCP, A2A, UCP, AP2, A2UI, and AG-UI) and the specific problem each one solves.
• The 'Start with MCP' strategy for connecting agents to tools and data sources without writing custom integration code.
• A hands-on look at building a restaurant supply chain agent that automates inventory, specialist quotes, and secure payment authorization.

👉 View Day 21 Drop Here

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Happy building!
The Advent of Agents Team

© 2026 Google Cloud · Season 2 · Spring Edition