Agent2Agent (A2A) is an open protocol designed to help independently built software agents discover one another, exchange information and coordinate tasks across system boundaries. A2A World covers the protocol as an independent publication and is not the protocol steward.
A2A in one sentence
A2A gives agents a common way to advertise capabilities, accept tasks, communicate state and return results without requiring every organization to build a proprietary point-to-point integration.
Agent Cards and discovery
Agent Cards provide machine-readable metadata that can describe an agent's capabilities, endpoint and supported interaction patterns. The concept matters because discovery is a prerequisite for interoperable agent networks.
A2A vs MCP
A useful architectural distinction is that MCP connects an agent to tools and resources, while A2A connects agents to other agents. They can be complementary rather than competing layers.
Why enterprises care
Interoperability can reduce vendor lock-in, simplify cross-platform coordination and make long-running multi-agent workflows easier to govern. Production adoption still requires identity, authorization, observability, security and policy controls around the protocol layer.