Microsoft Agent Framework Harness and Hosted Agents Reach General Availability

Microsoft’s Agent Framework now ships a supported runtime. At Build 2026 the company moved the Agent Harness, the GitHub Copilot and Claude Agent SDK connectors, and the orchestration patterns to stable release; the harness and Foundry Hosted Agents have since reached general availability. The change is less a new agent library than a supported path from build-time SDKs to run-time operations.

The product surface now spans three layers that previously sat outside a single supported stack. The Agent Harness is the runtime that hosts and controls agent execution. Connectors for GitHub Copilot and the Claude Agent SDK plug external agent implementations into that runtime instead of forcing a single in-house agent API. Orchestration patterns sit on top so multi-step and multi-agent flows share the same harness rather than ad hoc glue. Foundry Hosted Agents complete the picture as the managed hosting option for teams that do not want to operate the harness themselves.

For engineers and builders the practical shift is operational, not conceptual. Building an agent in an SDK is no longer the hard part; getting a governed place to run it—with connectors, orchestration, and a stable harness—is. Teams that already use Copilot or Claude-based agents can route those agents into Microsoft’s runtime instead of maintaining a separate execution environment. Teams standardizing on Azure or Foundry get a first-party path from prototype agents to Hosted Agents without inventing their own control plane.

Market context is a move from agent construction kits to agent platforms. Vendors have been racing to ship SDKs; fewer have shipped a supported runtime, managed hosting, and cross-vendor connectors under one release. Microsoft is positioning the Agent Framework as the place agents run under policy and lifecycle control, not only the place they are coded. That puts it in competition with other cloud and platform vendors that treat agents as long-running, governed workloads rather than chat demos.

Watch two things next: whether production teams adopt Foundry Hosted Agents as the default deploy target, and how deep the Copilot and Claude connectors go in day-to-day orchestration. If the harness becomes the common runtime across those connectors, the Framework’s value is platform lock-in by convenience. If teams still run agents outside the harness for latency, cost, or control reasons, GA of the runtime will matter less than the SDK story it replaced.