I Built Multi-Agent Systems Before NEXT '26 — Here's What the New ADK, MCP & A2A Stack Actually Changes

This is a submission for the Google Cloud NEXT Writing Challenge I Built Multi-Agent Systems Before NEXT '26 — Here's What the New ADK, MCP & A2A Stack Actually Changes I'll be honest: when Google Cloud NEXT '26 started announcing updates to the agent platform, my first reaction wasn't excitement — it was relief. Over the past few months, I've been systematically building up on the Google Cloud agent ecosystem — starting from the Cloud Technical Series OnBoard Edition (January 2026, hands-on