winui

WinUI agents and skills for Windows app development

A GitHub Copilot, Claude Code, and OpenAI Codex plugin for building native Windows apps with WinUI 3 and the Windows App SDK to cover the end-to-end inner loop: scaffold → design → build → run → test → package → ship.

[!WARNING] 🚧 Preview · v0.x — expect breaking changes. Skill names, on-disk layout, agent configuration, analyzer rule IDs, and CLI tool surfaces are all subject to change without notice. There is no SemVer commitment until v1.0. Pin to a specific commit if you need stability today. Outputs are suggestions, not authoritative answers — review them before committing or shipping anything they produce.

Install

The plugin requires GitHub Copilot (winget install GitHub.Copilot), Claude Code, or OpenAI Codex installed.

Git (winget install Git.Git) is required for installing pluggins.

Option A — Just ask Copilot to do it

Paste this prompt into a Copilot CLI session. It installs the plugin and sets up every prerequisite in one shot:

Install the Copilot CLI plugin "winui" from microsoft/win-dev-skills, then set up my machine for WinUI 3 development. Specifically:

1. Run: copilot plugin marketplace add microsoft/win-dev-skills
2. Run: copilot plugin install winui@win-dev-skills
3. Make sure these prerequisites are present (check first; .NET only installs if missing, but WinApp CLI and templates always upgrade to latest):
   - .NET SDK >= 8.0 (run `dotnet --list-sdks`; if none >= 8.0, `winget install --id Microsoft.DotNet.SDK.10 --exact --silent --accept-package-agreements --accept-source-agreements`)
   - WinApp CLI: must be >= 0.3 (parse `winapp --version`); if missing or older, `winget install --id Microsoft.WinAppCLI`. THEN regardless run `winget upgrade --id Microsoft.WinAppCLI` to get the latest.
   - WinUI 3 templates: always run `dotnet new install Microsoft.WindowsAppSDK.WinUI.CSharp.Templates` (after refreshing $env:Path) — it upgrades in place if already installed.
   - Developer Mode (DWORD HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\AppModelUnlock\AllowDevelopmentWithoutDevLicense == 1) — ASK ME first before triggering UAC; if I decline, just print the elevated command for me to run later.
4. Print a short summary of what was installed vs already present, then tell me to start a new Copilot CLI, activate the "winui-dev" agent, and to ask it to build an app.

Option B — Install the plugin yourself, then ask the agent to set up the rest

If you'd rather run the plugin commands by hand:

copilot plugin install winui@awesome-copilot

copilot plugin marketplace add microsoft/win-dev-skills
copilot plugin install winui@win-dev-skills

claude plugin marketplace add microsoft/win-dev-skills
claude plugin install winui@win-dev-skills

Then start a new session and run the winui-setup skill with /winui-setup.

Once setup is done, try a real task:

"Build me a WinUI 3 markdown editor with live preview and a custom title bar"

What gets installed

Visual Studio with the WinUI workload is optional but recommended for the XAML-diagnostics workaround called out in the next section. Neither setup path will install it; if you want it, run:

winget install Microsoft.VisualStudio.Community --override "--add Microsoft.VisualStudio.Workload.Universal"