Found at “Announcing the Agent2Agent Protocol (A2A) - Google Developers Blog” on 2025-04-10 09:34:17 +02:00.

A2A is an open protocol that complements Anthropic’s Model Context Protocol (MCP), which provides helpful tools and context to agents. Drawing on Google’s internal expertise in scaling agentic systems, we designed the A2A protocol to address the challenges we identified in deploying large-scale, multi-agent systems for our customers.

Something that caught my attention was their mention of OpenAPI in the announcement:

A2A is designed to support enterprise-grade authentication and authorization, with parity to OpenAPI’s authentication schemes at launch.