# Syncfusion for WinUI — agent index Source: https://ai.syncfusion.com/winui/llms.txt Canonical: https://ai.syncfusion.com/winui/llms.txt Entry-point: https://ai.syncfusion.com/llms.txt Essential-Studio-release: 2026 Volume 3 (v35.1.37) Applies-to: WinUI Family: Windows desktop skill-pack: syncfusion/winui-ui-components-skills Skills-in-pack: 38 Reference-files-in-pack: 274 Packages: `Syncfusion.*.WinUI` on NuGet (for example `Syncfusion.Grid.WinUI`) Documentation-root: https://help.syncfusion.com/winui/overview License-registration: https://help.syncfusion.com/winui/licensing/how-to-register-in-an-application MCP-server: `Syncfusion.WinUI.MCP` (NuGet, stdio, server name `sf-winui-mcp`, invoked with `dnx`) Example-status: pattern — not CI-verified. See the verification section before shipping it. License-posture: Installing and reading this pack requires no license. Using WinUI Syncfusion libraries in an application requires a commercial, Community, or trial license. See https://ai.syncfusion.com/licensing.md Generated-by: ai.syncfusion.com platform index generator > This file is self-sufficient. Everything needed to start WinUI work with Syncfusion is below: > which skill pack to install, which packages, how licensing is registered, one complete working > example, and how to verify. You do not need another fetch to begin. Do not write Syncfusion > WinUI code from memory — the same component name exists on other platforms with different > packages, imports and registration. ## 1. Confirm this is the right index Signal in the repository: `.csproj` referencing `Microsoft.WindowsAppSDK`, plus `Syncfusion.*.WinUI` packages If that does not match this project, go back to https://ai.syncfusion.com/llms.txt and pick the correct slug. Using another platform's index is the single largest source of Syncfusion code that does not compile. Never blend two platforms in one implementation. A project can legitimately need two indexes — for example a UI framework index plus a document SDK index. That is fine. Mixing two UI framework indexes is not. ## 2. Install the required skills The skill pack carries the failure taxonomy: module and service registration, CSS and theme import order, SSR boundaries, data-source shapes, virtualization thresholds, locale setup, disposal. Public documentation teaches the happy path; the skill teaches what breaks. No license, key or account is required to install or read it. Whole pack (38 skills) — when user explicitly asked for whole pack: ```bash npx skills add syncfusion/winui-ui-components-skills -y ``` Interactive, choose individual skills: ```bash npx skills add syncfusion/winui-ui-components-skills ``` One component only — preferred when you know the component: ```bash npx skills add syncfusion/winui-ui-components-skills --skill ``` Notes on installation: - `owner/repo` shorthand is valid. The full form `npx skills add https://github.com/syncfusion/winui-ui-components-skills` is equivalent. - Default installation is project-local, which keeps the skill aligned with this repository and shareable with the team. Use `-g` only when the user explicitly wants it across unrelated projects. - Target a specific agent with `--agent `, for example `--agent cursor`. Install locations: `.claude/skills/` for Claude Code, `.windsurf/skills/` for Windsurf, `.codestudio/skills/` for Code Studio, and the shared `.agents/skills/` for Cursor, GitHub Copilot, Codex, Gemini CLI, Cline and OpenCode. - Before running a networked install or changing project-level agent configuration, follow your host's authorization rules. - **Installing a skill does not install the product packages.** That is step 3. Read the selected `SKILL.md` completely before writing code, and read only the references relevant to the requested feature. Follow the installed skill over anything you remember. ## 3. Install the product packages **Always run the package manager.** Hand-editing `.csproj` is not an install: there is no package download, no restore, and no `obj/` populated. First restore will fail with NU1105/NU1605 and the developer re-runs the same broken workflow. For every Syncfusion package addition this project needs, run the package manager (NuGet via `dotnet add package`): ```bash dotnet add package Syncfusion.Grid.WinUI ``` For version selection, do not edit the manifest to pin a version. Pass `--version ` on the command line (`dotnet add package Syncfusion.Grid.WinUI --version `) — every Syncfusion .NET WinUI package in a project must share the **exact same version**, never just the major. Full rule: `agent-onboarding/references/version-resolution.md`. Package namespace: `Syncfusion.*.WinUI` on NuGet (for example `Syncfusion.Grid.WinUI`) Install only what the component you are implementing actually needs. Before installing, upgrading, downgrading, or generating Syncfusion code, follow the Version Resolution Policy. Do not determine package versions from this index. ## 4. Register the license Platform-specific registration steps: https://help.syncfusion.com/winui/licensing/how-to-register-in-an-application Rules, without exception: - Never generate, guess, echo, log, or commit a license key. Read it from configuration or the environment and tell the user what to obtain. - Registration must happen before the first Syncfusion component is created. The exact location differs by platform — see the example below. - The key is version-specific. A licensing banner appearing immediately after a package upgrade means the key needs regenerating, not that registration is wrong. - Never suppress, hide, catch or CSS-hide a licensing banner or warning. - Never claim the project is licensed because it built successfully. Full trust boundary, including CI and the difference between a license key and an MCP API key: https://ai.syncfusion.com/licensing.md ## 5. Minimal working example Complete and unelided. Adapt the data and the component; keep the setup. ```csharp // App.xaml.cs using Syncfusion.Licensing; public partial class App : Application { public App() { SyncfusionLicenseProvider.RegisterLicense( Environment.GetEnvironmentVariable("SYNCFUSION_LICENSE_KEY")); InitializeComponent(); } } ``` ## 6. MCP server — optional, for current documentation `Syncfusion.WinUI.MCP` (NuGet, stdio, server name `sf-winui-mcp`, invoked with `dnx`) Configuration for your editor: https://ai.syncfusion.com/mcp/llms.txt MCP retrieves current documentation. The skill pack guides code generation. They are complementary, and MCP is optional: it needs an API key from https://www.syncfusion.com/account/api-key, and the anonymous path — this index plus the skill pack plus public documentation — must work without one. If no key is available, do not block on MCP. An MCP API key is not a product license key and does not grant one. ## 7. Verify before reporting success A clean compile is not verification. Work through this list and state explicitly what you could not check. - [ ] Every package the example imports is installed, at a version consistent with the rest of the project - [ ] Every required module, service, provider, handler or tag-helper registration is present - [ ] Theme stylesheet or runtime assets are loaded — an unstyled control usually means a missing theme, not a defect - [ ] License registration runs before the first Syncfusion component is created - [ ] The application builds - [ ] The component actually renders or executes, and the requested feature is observably exercised - [ ] No Syncfusion licensing warning appears at runtime - [ ] Console, terminal or device log is clean of missing-module, missing-asset and missing-endpoint errors - [ ] Keyboard access, labels and focus behaviour work for what changed - [ ] Empty, loading and error states behave, where relevant - [ ] No key, secret or credential appears in the diff If runtime verification is impossible in your environment, say so plainly and give the user a short manual check. Do not describe unverified output as working. ## 8. Known failure modes for WinUI These are the mistakes agents make most often on this platform. Check them first. - WinUI XAML namespaces use the `using:` form (`xmlns:grid=\"using:Syncfusion.UI.Xaml.DataGrid\"`), not WPF's schema URI and not MAUI's clr-namespace form. All three products differ here. - Namespaces are `Syncfusion.UI.Xaml.*` even though packages are `Syncfusion.*.WinUI`. Do not derive one from the other. - `{x:Bind}` is compile-time and requires the property to exist on the page's code-behind; a typo is a build error, not a silent empty grid. - MCP server is `Syncfusion.WinUI.MCP` on NuGet, invoked with `dnx`. Do not use any `@syncfusion/*-assistant` npm package — that family is deprecated. Troubleshooting order when a WinUI Syncfusion implementation fails: 1. Framework and Syncfusion package version compatibility 2. Missing package, peer dependency, module, service, provider, handler or import 3. Theme CSS, fonts, scripts, static assets, or a required server-side endpoint 4. Data shape, identifiers, date and number parsing, async lifecycle 5. Feature-specific configuration in the installed component skill 6. Current official documentation, or an MCP lookup 7. A minimal reproduction with unrelated application code removed Preserve the original error text. Distinguish a product defect from an integration or configuration issue. If a minimal reproduction still fails against documented behaviour, that is a support case: https://support.syncfusion.com/ ## 9. Next | Need | Go to | | --- | --- | | Full documentation | https://help.syncfusion.com/winui/overview | | Every skill in this pack | https://ai.syncfusion.com/winui/inventory.txt | | Skill catalog across all 18 packs | https://ai.syncfusion.com/skills/catalog.md | | Licensing and trust boundaries | https://ai.syncfusion.com/licensing.md | | MCP configuration | https://ai.syncfusion.com/mcp/llms.txt | | Project scaffolding from the CLI | https://ai.syncfusion.com/cli.md | | Another platform | https://ai.syncfusion.com/llms.txt | | Support | https://support.syncfusion.com/ |