MCP (Model Context Protocol) is essentially a protocol for tool access. It defines a standard way for large language models to interact with various tools, data, and resources. Simply put, MCP enables AI to use various functionalities, much like how programmers call functions.
A2A (Agent-to-Agent Protocol) focuses on agent collaboration. It establishes ways for intelligent agents to discover, communicate, and cooperate with each other, allowing different AI systems to work together like human teams.
Taken straight from this article:
https://a2aprotocol.ai/blog/a2a-vs-mcp