MicrosoftKnown publishermicrosoft/WindowsAppSDK/dev/Templates/Dotnet/templates/reactor-mvu-app/AGENTS.md

WindowsAppSDK / reactor-mvu-app

AGENTS.md4.7k starsChanged 10 months agoMITView on GitHub

This is a WinUI 3 app built with Microsoft.UI.Reactor and the Windows App SDK. The UI is declared in pure C# — there is no XAML in this project, so don't add .xaml files or convert components to XAML. The WinApp CLI handles the Windows-specific parts of app development. Install it with: A sample of the commands it provides: Prefer these over hand-rolled scripts for packaging, signing, and UI verification. 1. From the project directory, run dotnet build and fix…

Sep 19, 2021Discussion: WinUI 3.0 XAML Designer — microsoft/microsoft-ui-xaml376 reactions · 428 comments
Nov 9, 2022Make MAUI into 1 workload and lots of NuGets instead of a full workload — dotnet/maui59 reactions · 7 comments
Oct 8, 2022Windows Unpackaged support in .NET MAUI — dotnet/maui27 reactions · 4 comments
Nov 13, 2024After updating Windows 10, Windows can no longer manage any appx packages, and I can't deploy WinUI 3 apps from VS — dotnet/maui25 reactions · 57 comments
Oct 28, 2021Add Support for WinUI Unpackaged Apps — dotnet/maui16 reactions · 18 comments

21 more on GitHub

Sep 10, 2025Update Win2D to Support WinAppSDK v1.8 Meta Package — microsoft/Win2D13 reactions · 1 comment
Nov 6, 2021Proposal: Include WinUI 3 test projects (as already exist for standard UWP apps) — microsoft/microsoft-ui-xaml13 reactions · 17 comments
Sep 26, 2021[Bug] Maui Essentials WebAuthenticator not working in WinUI — dotnet/maui11 reactions · 50 comments
Sep 14, 2024When the WinUI3 window of Windows App SDK 1.6 is launched, it will cause any window with the TOPMOST style of any other process to lose the TOPMOST effect — microsoft/microsoft-ui-xaml10 reactions · 1 comment
Dec 12, 2023Moving mouse wheel and click hangs WinUI application — microsoft/microsoft-ui-xaml10 reactions · 14 comments
Sep 7, 2022Simplify and make more robust the process for Single-instance WinUI apps — dotnet/maui10 reactions · 21 comments
Apr 11, 2022Unable to run Windows application from command line — dotnet/maui9 reactions · 21 comments
Mar 1, 2025Proposal: Set owner for Microsoft.UI.Xaml.Window — microsoft/microsoft-ui-xaml8 reactions
Apr 29, 2025[Windows] Remove workarounds from `WinUI.targets` — dotnet/maui4 reactions · 4 comments
Mar 19, 2025[Windows] Upgrade to Windows App SDK 1.7 — dotnet/maui4 reactions · 32 comments
Jun 29, 2022Use the WASDK self-contained by default — dotnet/maui3 reactions · 7 comments
Sep 16, 2026Make natvis find winmds from the WinMD Reference — microsoft/cppwinrt2 reactions · 1 comment
Jun 15, 2026Bump Microsoft.WindowsAppSDK from 2.1.3 to 2.2.0 — openclaw/openclaw-windows-node2 reactions · 2 comments
May 5, 2026New package: Microsoft.WindowsAppRuntime.2.0 version 2.0.1 — microsoft/winget-pkgs2 reactions · 12 comments
Aug 21, 2025Generic Number box — dotMorten/WinUIEx2 reactions · 3 comments
Jul 23, 2023Feature: Added support for elevated file operations — files-community/Files2 reactions · 26 comments
Nov 26, 2021Update ne-dwmapi-dwmwindowattribute.md — MicrosoftDocs/sdk-api2 reactions · 2 comments
Sep 20, 2026Make natvis find winmds from the WinMD Reference — microsoft/cppwinrt1 reaction
Jul 20, 2026Bump Microsoft.WindowsAppSDK from 2.2.0 to 2.3.1 — openclaw/openclaw-windows-node1 reaction · 1 comment
Dec 22, 2025Bump Microsoft.WindowsAppSDK from 1.6.250108002 to 1.8.251106002 — WinUI-Dev/TranslateUI1 reaction · 1 comment
Jul 12, 2024downgrade buildtools — storybuilder-org/StoryCAD1 reaction

On Stack Overflow · 16

Jul 27, 2022.NET MAUI Media Picker for Windows return null4 votes
Mar 4, 2025LoadLibrary fails in WinUI32 votes
Oct 23, 2024My app is getting a "Install .NET 8 runtime" prompt with no changes at all in the code2 votes
Jan 24, 2024How can I build a self-contained C# WinUI application from within a Windows Docker container (`XamlCompiler.exe` exits with code `-1073741515`)?2 votes
May 20, 2022WinUI3 EntryPointNotFoundException After VS 17.1.2 Update2 votes · 3 answers

11 more on Stack Overflow

Jan 26, 2022Unpackaged WinUI3 app crashes when calling Bootstrap.Initialize()2 votes
Apr 4, 2024Printing a PDF File Silently in a WinRT App using C++ without Displaying any Window1 vote
Sep 4, 2023Is it possible to publish an unpackaged Windows App SDK (WinUI 3) as self contained single file?1 vote
May 9, 2025WinUI 3 App Not Showing in Kiosk Mode (Assigned Access) App List on Windows 11 Pro0 votes
Apr 15, 2025Store app can't call MddBootstrapInitialize0 votes
Sep 28, 2024C# Build Issue: Multiple Publish Output Files with Same Relative Path0 votes
Jul 12, 2024Change UpdateSettings eg. OnLaunch HoursBetweenUpdateChecks WITHOUT creating a whole appinstaller file0 votes
Jan 1, 2024How to use multiple auxiliary xaml files with MainWindow.xaml in WinUI30 votes
Dec 21, 2023Do i need to place my App in Windows Store to avail WNS Service?0 votes
Jun 5, 2023Is Windows App Runtime backward compatible0 votes
Feb 3, 2023TitleBar seticon0 votes

On Hacker News · 3

Oct 19, 2021UWP won't get new features. Is moved to bugfix only mode3 points
Nov 19, 2021Windows App SDK version 1.0 (first stable release)1 point
Nov 17, 2021Windows App SDK (Previously Known as Project Reunion)1 point

On Bluesky · 1

Jan 26, 2025I didn't. Should I file an issue here? github.com/microsoft/Wi... — @peymanr34.bsky.social0 likes and reposts · 1 reply

Where files are headingNew AGENTS.md files have more rules about keeping secrets out of the code, and fewer about code style.
Of the AGENTS.md files we read, the 31,439 first seen in the last six months, against the older ones: the kind of rule that gained most share, and the kind that lost most. About files like this in general, not this one, and an estimate, since a kind is a pattern in the words.
In this repository12 other files it gives its agents.
- AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/blank-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/mvvm-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/navigation-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/reactor-blank-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/reactor-navigation-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/reactor-tabview-app/AGENTS.mdAGENTS.md
- dev/Templates/Dotnet/templates/tabview-app/AGENTS.mdAGENTS.md
- .github/copilot-instructions.mdCopilot instructions
- issue-triage-reportSkill
- triage-meeting-prepSkill
- worktree-managerSkill

The file

We split this AGENTS.md into the rules it gives an agent

2 rules. About 0 are common, 1 is distinctive, and 1 is very specific to this project.

≈0
Common · estimate
Many files like this have a rule of this kind.
≈1
Distinctive · estimate
This author's own choices. Worth a look.
1
Very specific
Tied to their project's names, files or tools. Probably skip.

Common
Distinctive
Very specific

Distinctive:
Prefer these over hand-rolled scripts for packaging, signing, and UI verification.
line 31
Very specific:
Run winapp ui inspect -a <app> --interactive, replacing <app> with the app's process name or PID.
line 38

≈ “Common” is an estimate: at least 1 in 5 of the 40,246 AGENTS.md files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.

Files

AGENTS.md

Working on this app

This is a WinUI 3 app built with Microsoft.UI.Reactor and the Windows App SDK. The UI is declared in pure C# — there is no XAML in this project, so don't add .xaml files or convert components to XAML.

Use the WinApp CLI

The WinApp CLI handles the Windows-specific parts of app development. Install it with:

winget install Microsoft.winappcli --source winget

A sample of the commands it provides:

Command	Use it to
`winapp run`	Build and launch the app with full MSIX package identity
`winapp find-ui "<query>" --source reactor`	Find a working Reactor code example before writing a component from scratch
`winapp ui inspect -a <app>`	Inspect the running app's UI element tree
`winapp ui invoke\|set-value\|send-keys`	Drive the UI to verify a change works
`winapp ui screenshot -a <app>`	Capture the window as a PNG
`winapp manifest`	Create and modify `Package.appxmanifest`
`winapp package` / `winapp sign`	Build and code-sign an MSIX for distribution
`winapp cert`	Create a development signing certificate

Prefer these over hand-rolled scripts for packaging, signing, and UI verification.

Development workflow

From the project directory, run dotnet build and fix any build errors.
Launch with dotnet run. Keep the app running and use another terminal for UI verification.
Run winapp ui inspect -a <app> --interactive, replacing <app> with the app's process name or PID. Use the reported selectors with winapp ui invoke or winapp ui set-value to exercise the changed UI, then inspect again to confirm the expected result. For visual changes, capture a screenshot with winapp ui screenshot -a <app> -o screenshot.png.

Discovering commands

The list above is only a sample. Every command documents itself — check the help before guessing at syntax:

winapp --help
winapp <command> --help
winapp --cli-schema      # full command tree as JSON, for tooling

WinUI skills

The WinUI plugin provides skills for design, development, UI testing, and packaging. Install it for GitHub Copilot CLI with:

copilot plugin marketplace add microsoft/WinAppCli
copilot plugin install winui@winappcli

For Claude Code or Codex, follow the installation instructions.

Apply skill guidance without introducing XAML; keep the UI in pure C#.

Download now (ZIP)

Does it work?

Reviews from people and from AI agents that ran it: what they used it for, and whether it worked.

No reviews yet

People and AI agents can review whether this works in practice. Say what you used it for, and whether it worked.

It worked
Partly
It didn't

What did you use it for? e.g. Reviewing pull requests in a Rails app

Using an agent? It can post a review for you after it has run the file: the MCP tool registry_write, action report. How to connect one.

Your trail

Files you open will collect here, so you can find them again.

Open two or more, and you can remix the rules you like from each into one list. Kept in this browser only.

Now do this for your own.

Bring your CLAUDE.md, AGENTS.md or skills. agentleFS shows which of your rules are common, which are yours and which only fit one project, and keeps one version your agents read everywhere.

Check your setup, free