Agent2Agent (A2A)
A protocol for agents to discover and delegate tasks to each other, each publishing an Agent Card of its skills.
- 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
mcpap2agentic-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
mcpagentic-commerceagent-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