microsoft/autogen

AutoGen is the category-defining framework for multi-agent systems. With nearly 57,000 stars, it has achieved massive escape velocity compared to earlier orchestration attempts. Its primary defensibility stems from its community-driven ecosystem of 'agent recipes' and its role as the research-to-production bridge for Microsoft's agentic AI strategy. While competitors like CrewAI offer better UX for business processes and LangGraph offers more granular state-machine control, AutoGen remains the de facto standard for open-ended multi-agent research and complex conversation patterns. The 'Frontier Risk' is medium because while OpenAI (Assistants API, Swarm) and Google are building native agentic features, AutoGen's provider-agnostic nature and support for local models (via Ollama/LiteLLM) provide a level of flexibility and data privacy that frontier labs cannot easily offer without cannibalizing their own API ecosystems. The project is currently undergoing a significant architectural rewrite (v0.4) to decouple core agent logic from communication protocols, which suggests a transition from a library to a robust, infrastructure-grade distributed systems framework. Platform domination risk is medium because although it is a Microsoft project, its open-source nature allows it to serve as a neutral ground across Azure, AWS, and GCP environments.