Microsoft Agent Framework adds GitHub Copilot SDK backend, Agent Harness and CodeAct at Build 2026

Microsoft Agent Framework Blog·medium signal

At Build 2026 (June 2–3) the Microsoft Agent Framework team announced that MAF — which hit 1.0 GA on 2026-04-02 as the AutoGen + Semantic Kernel convergence — can now build agents on the GitHub Copilot SDK as a backend, bringing Copilot's shell execution, file operations, URL fetching, and MCP server integration into the standard MAF programming model across .NET and Python. New additions include an agent harness pattern, hosted agents, and CodeAct (code-as-action) execution. This positions MAF as a production runtime that unifies coding-agent primitives with multi-step multi-agent workflows.