AG2 (AutoGen 2.0) Review 2026

AG2 is the open-source AgentOS for building multi-agent AI systems — evolved from Microsoft's AutoGen and now community-maintained. It provides production-ready agent orchestration with conversable agents, group chat, swarm patterns, and human-in-the-loop workflows, letting development teams build complex AI automation without vendor lock-in.

AG2, formerly AutoGen, is the open-source AgentOS that has become the go-to framework for developers building multi-agent AI systems in 2026. Born from Microsoft Research's pioneering AutoGen project, AG2 is now independently maintained by a community of contributors spanning multiple organizations, operating under the Apache 2.0 license with zero commercial restrictions. The framework's guiding principle — "Build Systems, Not Prompts" — reflects its focus on structured agent architectures rather than prompt engineering workarounds.

At its core, AG2 provides the Conversable Agent abstraction: autonomous AI entities that can send messages, receive responses, invoke tools, execute code, and collaborate with other agents through well-defined conversation protocols. This is fundamentally different from the chain-of-prompts approach used by simpler frameworks. In AG2, agents are independent actors with their own system prompts, tool access, memory, and decision-making logic. You compose them into systems using conversation patterns — and this is where AG2's depth separates it from the competition.