Agent ↔ agent

Agent2Agent Protocol

Lets independent agents discover each other, delegate tasks and stream results, whoever built them.

Browse A2A agents
Status
Stable, v1.0.1 (May 2026)
Governance
Agentic AI Foundation since August 2026. Created by Google in April 2025.
Sources
Project siteSpecification

What to know

  • v1.0.0 shipped on 12 March 2026 with breaking changes from 0.3; v1.0.1 followed on 28 May 2026.
  • Agents publish an Agent Card at /.well-known/agent-card.json; authenticated callers can fetch more through GetExtendedAgentCard.
  • Three formal bindings: JSON-RPC 2.0, gRPC and HTTP+JSON (REST).
  • Agent Cards can be signed with JWS (RFC 7515) over JSON Canonicalization (RFC 8785).

When to use it

When your agent must hand work to an agent you do not control, such as a vendor's support agent or a partner's booking agent. For calling tools, use MCP instead.

Related standards

MCP · Model Context ProtocolSKILL.md · Agent SkillsAGENTS.md · AGENTS.mdACP · Agent Client Protocol

Reviewed Oct 5, 2026. Spotted something out of date? Email hello@agentatlas.dev.