Copilot in Visual Studio Just Got a Major Upgrade

Copilot Chat in Visual Studio just got a new engine. Starting with Visual Studio 2026 version 18.12, it runs on the Microsoft Copilot SDK developed by GitHub, the same technology powering GitHub Copilot CLI, the GitHub Copilot app, and VS Code. It’s on by default, and it’s a major upgrade: same models, more tasks solved, new ways to work.

We put the previous and new Copilot experiences through over one hundred coding tasks. The new experience came out ahead with every model we tested, across capability levels and providers, resolving up to 21 more tasks.

The chat itself is better too: you get shorter, more focused answers, you can steer Copilot mid-task and see what each request costs.

More Tasks Solved

To measure what matters to .NET developers, the .NET team built a benchmark from real issues in real C# projects, across .NET Framework and .NET Core, Azure and Aspire, and WinForms and desktop apps. We ran both Copilot chat experiences through 157 of its tasks. A task counts as resolved only when its failing tests pass without breaking any that already passed.

The new engine has also been tested on C++, Python, and a range of other languages.

One example from our own backlog: a user reported that long answer choices in Copilot’s questions were getting cut off. We asked Copilot to help reproduce it, once in the previous experience and once in the new SDK-powered experience. The previous experience came back with steps for us to reproduce it by hand. The new one did something we didn’t expect: it realized it was running inside the very chat window that had the bug, so it reproduced the problem right there.

Same Models, Better Harness

On its own, a model reads text and writes text. It can’t open your solution, edit a file, or run your tests. The harness is everything around the model that turns text into real work: what the model sees, which tools it can use, what it remembers, and what it’s allowed to touch. Give the same model a better harness, and you get better results.

Through the SDK, Copilot in Visual Studio now runs on the Microsoft Copilot harness. It’s battle-tested at the scale of millions of users, and GitHub designed it to be fast and predictable. Here’s what you’ll notice:

• It finishes the job. The harness keeps Copilot going until the task is actually done.
• It gets to the point. One developer described the experience as “Less chatter, more quality results for large tasks”.

New in Copilot Chat

The new engine also changes how you work with Copilot. Here’s what you won’t find in the previous experience.

• Steer it while it works. No more waiting for Copilot to finish before you change course. Type a new instruction and press Enter, and Copilot picks it up mid-task. Until it does, your message is marked Pending, and you can select the X to take it back.

• See what Copilot actually did. Every step shows what came back, not just what Copilot tried. Expand a step to see the results, open them in the editor, or copy the exact command Copilot ran.
• Watch subagents at work. When Copilot hands off part of a task to a subagent, the subagent gets its own card showing which model it’s using and every step it takes, live.

• Work beyond your solution. Point Copilot at any folder on your machine from the chat header or attach whole folders as context.

• Get a second opinion. With Agent selected, type / to call on one of the built-in agents. /security-review runs a security-focused review of your changes to find vulnerabilities, and /rubber-duck has a different model critique Copilot’s plan before it acts.

Still Unmistakably Visual Studio

Because it’s the same technology, Copilot behaves more consistently across Visual Studio, VS Code, Copilot CLI, and the GitHub Copilot app. Write an agent skill once, and it works in all four without modifications. Improve the harness, and every surface benefits.

But the same engine doesn’t mean a one-size-fits-all experience. Copilot still works with the tools you rely on in Visual Studio. Specialized agents help you debug, profile, fix build failures, modernize .NET apps, and speed up C++ builds. Built-in agent skills add .NET and Azure expertise, alongside the MCP servers you’ve already set up.

Try It Today

Update to Visual Studio 2026 version 18.12, open Copilot Chat, and give it a task from your own backlog. That bug you’ve been putting off? Start there.

We’re still bringing over a few features from the previous experience, like plan mode and chat exports. If you rely on them, or need to switch back for any reason, you can turn off “Use new Copilot chat experience” in Tools > Options > GitHub > Copilot > Copilot Chat, restart Visual Studio, and please take some time to tell us why.

Tell us what Copilot gets right and where it needs to improve. Report issues through Help > Send Feedback > Report a Problem, or share your ideas on Developer Community.

Happy coding!