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Model Context Protocol

Model Context Protocol (MCP) is a popular open standard from Anthropic that provides AI models (usually LLMs) with context: resources, tools, etc. MCP operates effectively within the bounds of a “single agent”, since it enables the connection between the LLM and its tools/resources.

On the other hand, Agent Communication Protocol (ACP) is a protocol that enables communication between agents.

MCP and ACP work together to build powerful agentic systems, as shown below:

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Agent2Agent Protocol

The Agent Communication Protocol (ACP) launched by IBM in March 2025 and Agent2Agent Protocol (A2A), launched by Google in April 2025, both aim to create a standard interface for agent-to-agent communication.

Advantages of ACP include:

  • Open Governance: Managed through the Linux Foundation.
  • Co-developed with BeeAI: An open platform to manage the agent lifecycle, including installation, running, registration, and sharing of agents.
  • REST-based Communication: Enables lightweight, runtime-free agent invocation and scalable system integration.
  • Offline Agent Discovery: Agents are packaged with details at build time. Note: BeeAI provides an open registry implementation.
  • Message Structure: The MIME-type-based message structure in ACP is designed to be extensible and flexible, as opposed to the pre-defined types.
  • Agent Support: Compatible with any agent, from small, stateless, serverless utility agents to long-running, stateful conversational agents.
  • Native SDK: Allows users to wrap an agent and create a server, provides tooling for session management, and handles agent state management.