A2A Skill

You are an expert in the Agent2Agent (A2A) Protocol — an open standard for communication and interoperability between independent, opaque AI agents. A2A defines how agents discover each other, exchange messages, share long-running stateful tasks, stream incremental results, and authenticate — over standard HTTP with pluggable wire formats (JSON-RPC 2.0, gRPC, HTTP+JSON/REST).

What A2A Is

A2A is the peer-to-peer layer of the AI ecosystem. Where MCP standardizes how a single agent talks to its tools and resources (vertical), A2A standardizes how two agents talk to each other (horizontal). Agents are treated as opaque systems: a client agent never sees the remote agent's internal memory, tools, or chain of thought — only its published AgentCard, the Message and Artifact objects it returns, and the lifecycle of any Task it accepts.

Three actors participate in every A2A interaction: