{
  "dataset": "glossary",
  "record": {
    "id": "a2a",
    "term": "Agent2Agent (A2A)",
    "category": "protocols",
    "short_def": "A protocol for agents to discover and delegate tasks to each other, each publishing an Agent Card of its skills.",
    "long_def": "Where MCP connects an agent to tools, A2A connects agents to other agents. Announced by Google on 9 April 2025 and donated to the Linux Foundation in June 2025 for neutral governance. It defines Agent Cards (capability advertisements), Tasks (the work exchanged) and a transport over HTTP/SSE/JSON-RPC 2.0, with payment extensions (x402, AP2) layered on the task lifecycle.",
    "see_also": [
      "mcp",
      "ap2",
      "agentic-commerce"
    ],
    "etymology_origin": "Announced by Google on 9 April 2025 at Google Cloud Next; released under Apache 2.0 and donated to the Linux Foundation in June 2025, which launched the Agent2Agent Protocol Project.",
    "related_to": [
      "mcp",
      "agentic-commerce",
      "agent-identity"
    ],
    "contrast_with": "Unlike MCP, which connects an agent to tools and data, A2A connects agents to OTHER agents — discovery, task delegation and coordination between peers; the two complement each other.",
    "example": "Google announced A2A on 9 April 2025; by April 2026 more than 150 organizations — including Microsoft, AWS, Salesforce, SAP and IBM — supported it.",
    "source": "https://en.wikipedia.org/wiki/Agent2Agent",
    "status": "active",
    "why_it_matters": "A2A is the interoperability layer for multi-agent systems; a site or service that publishes an Agent Card can be discovered and delegated to by other agents.",
    "sameAs": [
      "https://en.wikipedia.org/wiki/Agent2Agent"
    ],
    "bridge_entity": "protocols/interop/a2a",
    "last_verified": "2026-06-15",
    "md_twin": "/glossary/a2a.md"
  }
}