A2A (Agent2Agent)

In plainer words

A2A (Agent2Agent) is an open protocol, led by Google, that lets "AI agents built by different companies talk to each other." In reality agents come from all sorts of vendors and frameworks that don't interoperate; A2A defines a common language so one agent can discover another, delegate a task, and get results back. It's often mentioned alongside MCP, but they split the work: MCP lets one agent "use tools and data" (agent → tool); A2A lets "agents talk and collaborate with each other" (agent ↔ agent). One is hands, the other is social. Why does it relate to payments? Once agents delegate to and hire each other, they naturally pay each other. Agents that can talk (A2A) + pay (x402/AP2) + trust each other (ERC-8004/KYA) — put together, that's the seed of an "agent economy." And every time an agent pays an agent, someone has to ask, before settlement, whether the money is clean.