Microsoft offers the Copilot harness through Foundry
The harness behind Microsoft and GitHub Copilot is available as a Foundry SDK or a managed cloud runtime, with model choice left to you.
Official source (opens in a new tab)
Microsoft's blog on 28 October 2026 says the Copilot harness is available through Microsoft Foundry. Microsoft describes a harness as the layer around a model: instructions, context, the execution environment, and controls. The post says this harness already powers Copilot Code, Copilot Studio, the GitHub Copilot app, the CLI, Visual Studio Code, and more. You can download an SDK or run the harness in the cloud, managed by Foundry. Microsoft says it runs the agent loop and sandbox. You bring the instructions, skills, tools, and model choice.
The post says the harness supports MCP, agent skills, and agent plugins, and that it works across more than 20 frontier models plus a bring-your-own key. Microsoft says a port of the runtime to Rust reduced session overhead and time to first token. The post does not list a price.
Who it's for: a developer or an enterprise team that wants Microsoft's agent loop and sandbox, and will pick the model separately.
Fits: Best Agent Builder stays n8n. A Foundry harness is a runtime for agents you assemble. It is not the workflow tool a team hands off with a human approval step. The agent builder guide and n8n alternatives are unchanged. The verdict is unchanged.