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Agent Commerce
A2A
An open protocol for communication between AI agents built by different vendors or frameworks. It defines three things: Agent Cards, metadata documents advertising what an agent can do, Tasks, the structure of work exchanged, and a transport over HTTP, SSE and JSON-RPC 2.0. Donated by Google to the Linux Foundation in 2025.
Why it matters
MCP connects an agent to tools; A2A connects agents to each other. The distinction decides which problems each can solve, and they are routinely conflated.
In practice
Mostly relevant if you run multiple agent systems that need to cooperate. For a single-vendor stack it is infrastructure you will not touch directly.
Related terms