--- title: Introducing the Microsoft Copilot harness: Unlocking the... description: Microsoft is making its Copilot harness, the orchestration layer around the model, available through Microsoft Foundry. The harness already powers Copilot... canonical: https://daily.dev/posts/introducing-the-microsoft-copilot-harness-unlocking-the-potential-of-truly-multi-model-agentic-work-shfpdzh7p twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Introducing the Microsoft Copilot harness: Unlocking the potential of truly multi-model agentic work | daily.dev og:description: Microsoft is making its Copilot harness, the orchestration layer around the model, available through Microsoft Foundry. The harness already powers Copilot... og:url: https://daily.dev/posts/introducing-the-microsoft-copilot-harness-unlocking-the-potential-of-truly-multi-model-agentic-work-shfpdzh7p og:image: https://api.daily.dev/og/posts/ShfpdzH7p.png og:image:alt: Introducing the Microsoft Copilot harness: Unlocking the potential of truly multi-model agentic work og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Introducing the Microsoft Copilot harness: Unlocking the potential of truly multi-model agentic work **[Microsoft](https://daily.dev/sources/microsoft)** · 4 min read · 1 upvotes · 0 comments ## Summary Microsoft is making its Copilot harness, the orchestration layer around the model, available through Microsoft Foundry. The harness already powers Copilot Code, Copilot Studio, the GitHub Copilot app, the CLI, and VS Code. It supports 20+ frontier models plus bring-your-own-key, routing tasks to the right model. Its runtime was recently ported to Rust, improving performance and reducing session overhead and time-to-first token. The SDK is downloadable, or developers can run the harness in the cloud managed by Foundry. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the Microsoft Copilot harness and what does it do? It is the orchestration layer around an AI model that gives an agent instructions, context, execution environment, and controls to do real work, including tool use and long-running tasks. Built by GitHub engineers, it already powers Copilot Code, Copilot Studio, the GitHub Copilot app, the CLI, and VS Code, and supports 20+ frontier models plus bring-your-own-key. _Developers evaluating agent orchestration layers can track how Copilot's harness evolves on daily.dev._ ### How is the GitHub Copilot harness runtime built, and what language is it written in? The harness runtime was recently ported to Rust, which GitHub says resulted in industry-leading performance along with reductions in both session overhead and time-to-first token. It runs at the scale of millions of users across hundreds of real-world use cases, serving surfaces like Copilot Code, Copilot Studio, the GitHub Copilot app, the CLI, and VS Code. _Teams weighing Rust rewrites for performance-critical services can follow similar migrations on daily.dev._ ### How can I use the Copilot harness to build my own AI agents outside of GitHub products? The Copilot harness is now available through Microsoft Foundry as a fully managed service, or via a downloadable SDK to run yourself. It lets you choose from 20+ frontier models or bring your own key, routes tasks to the right model, and runs the agent loop and sandbox with governance and optimization, while you supply instructions, skills, tools, and model choice. _Developers choosing an agent framework for multi-model workflows can compare options on daily.dev._ ## Similar posts on daily.dev - [Copilot SDK is now generally available](https://daily.dev/posts/copilot-sdk-is-now-generally-available-bkergfcmj) · GitHub Changelog · 1 upvotes · 0 comments - [Building AI agents with the GitHub Copilot SDK](https://daily.dev/posts/building-ai-agents-with-the-github-copilot-sdk-tauv44gc4) · InfoWorld · 1 upvotes · 0 comments - [You don't need to build your own agent harness](https://daily.dev/posts/you-don-t-need-to-build-your-own-agent-harness-lqcnyprbc) · The Art of Simplicity · 1 upvotes · 0 comments --- Tags: [#github](https://daily.dev/tags/github), [#rust](https://daily.dev/tags/rust), [#mcp](https://daily.dev/tags/mcp), [#agentic-ai](https://daily.dev/tags/agentic-ai), [#microsoft-foundry](https://daily.dev/tags/microsoft-foundry) [View this post on daily.dev](https://daily.dev/posts/introducing-the-microsoft-copilot-harness-unlocking-the-potential-of-truly-multi-model-agentic-work-shfpdzh7p) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Introducing the Microsoft Copilot harness: Unlocking the potential of truly multi-model agentic work","url":"https://daily.dev/posts/introducing-the-microsoft-copilot-harness-unlocking-the-potential-of-truly-multi-model-agentic-work-shfpdzh7p","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/introducing-the-microsoft-copilot-harness-unlocking-the-potential-of-truly-multi-model-agentic-work-shfpdzh7p"},"datePublished":"2026-10-28T16:55:45.628Z","dateModified":"2026-10-30T15:09:15.730Z","description":"Microsoft is making its Copilot harness, the orchestration layer around the model, available through Microsoft Foundry. 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