Google's Agent2Agent Protocol Explained

Google's Agent2Agent (A2A) protocol is an open-source communication standard designed to facilitate seamless interactions between autonomous AI agents across different platforms and vendors by using familiar web technologies like JSON-RPC 2.0, HTTP/HTTPS, and Server-Sent Events. Governed by the Linux Foundation, A2A aims to address vendor lock-in and integration complexities that typically consume 20-40% of engineering resources by providing a standardized layer for agent discovery, authentication, and collaboration. Unlike the MCP protocol, which focuses on connecting agents to tools, A2A enables peer-to-peer agent coordination, supporting complex workflows with enterprise-grade security measures such as OAuth 2.0, API Keys, and mTLS. Despite being in its early adoption phase with limited production deployments as of early 2025, the protocol has gained traction with Microsoft and partnerships with several technology firms. Enterprises are encouraged to consider phased adoption and proof-of-concept validation to navigate the risks and leverage the protocol's interoperability benefits in multi-agent systems.