Beyond the Hype Part 2: Enter Google's A2A Protocol - Complementing MCP for Agent Collaboration

Google's Agent 2 Agent (A2A) protocol complements Anthropic's Model Context Protocol (MCP) by focusing on inter-agent communication, while MCP handles agent-tool interaction. A2A standardizes how AI agents discover, communicate, and coordinate actions using an open protocol. Key A2A concepts include agent discovery via "Agent Cards," task management, and multi-modal messaging. A2A leverages HTTP, JSON-RPC 2.0, and Server-Sent Events for efficient communication and task handling. Unlike MCP's stateful approach, A2A primarily uses stateless HTTP requests, improving scalability. A2A doesn't directly address tool integration; it assumes agents already have methods for accessing tools. The synergy between A2A and MCP allows for complex workflows where agents collaborate using A2A and access tools via MCP. Examples include car repair shops and multi-stage hiring processes. A2A differs from other standards like Agents.json and llms.txt by focusing on general-purpose inter-agent communication. The combined use of MCP and A2A enables a powerful two-layer model for building sophisticated AI systems. This two-layer approach promises greater modularity, interoperability, and innovation in the AI ecosystem.