Three things worth knowing about Microsoft Agent Framework python-1.19.0: (1) four BREAKING changes land together, covering HTTP cookie persistence, MCP skill archive format, MCP session scoping, and Redis history key scoping; (2) a new generic vector store provider protocol ships with three new connectors at once — MongoDB (alpha), Azure DocumentDB (alpha), and Azure Cosmos DB NoSQL; (3) built-in orchestration workflows now have stable names and registered checkpoint types, so the built-in sequential/concurrent/handoff/group-chat patterns can be restored after a restart, not just custom workflows.
Parallel + nested agent spawns can burn 200K+ tokens in a single conversation turn. From Anthropic to Microsoft, the industry is converging on tiered responses: compress → downgrade → stop, rather than a binary kill switch.
By 2026 nearly every mainstream coding agent supports subagents. Design philosophies split three ways: deterministic scripted orchestration (Claude Code Workflow), model-driven autonomy (Codex, Devin), and IDE command-center integration (Windsurf 2.0, VS Code). This overview maps product positioning, a capability matrix, and the design-philosophy spectrum.
Microsoft merged Semantic Kernel and its own AutoGen into Microsoft Agent Framework, which hit 1.0 GA on 2026-04-02 for .NET and Python (Go is still public preview). The absorbed autogen-agentchat has not shipped since 2025-09-30. But AG2, the fork on the original authors' side, never merged — it shipped 1.0.2 six days ago, and `pip install autogen` gets you AG2, not Microsoft. This post covers MAF's abstractions, the migration clock, and how to read the tangle of names.