What happened
Microsoft folded AutoGen — its research-driven multi-agent conversation framework — into Semantic Kernel, its enterprise agent SDK, and shipped the result as a single Microsoft Agent Framework in October 2025. AutoGen is now in maintenance mode: it still gets security patches, but new features and new projects are directed to Agent Framework instead.
This isn't a rename. AutoGen and Semantic Kernel had genuinely different design centers — AutoGen optimized for flexible, research-friendly multi-agent conversations; Semantic Kernel optimized for enterprise SDK consistency across Python, C#, and Java, with tighter Azure integration. Agent Framework is Microsoft's attempt to keep AutoGen's conversation patterns while giving them Semantic Kernel's production and governance story.
Why this matters if you're building agents now
If you're starting a new project today, start on Agent Framework, not AutoGen — you'd otherwise be building on a track Microsoft has already said is winding down. If you have an existing AutoGen system in production, you don't need to panic-migrate; maintenance mode means it keeps working and keeps getting patched. But budget the migration as planned technical debt rather than something to revisit "eventually" — the gap between AutoGen and current tooling only grows.
