Winmd API Search Agent Skill

WinMD API Search

This skill helps you find the right Windows API for any capability and get its full details. It searches a local cache of all WinMD metadata from:

• Windows Platform SDK — all Windows.* WinRT APIs (always available, no restore needed)
• WinAppSDK / WinUI — bundled as a baseline in the cache generator (always available, no restore needed)
• NuGet packages — any additional packages in restored projects that contain .winmd files
• Project-output WinMD — class libraries (C++/WinRT, C#) that produce .winmd as build output

Even on a fresh clone with no restore or build, you still get full Platform SDK + WinAppSDK coverage.

When to Use This Skill

• User wants to build a feature and you need to find which API provides that capability
• User asks "how do I do X?" where X involves a platform feature (camera, files, notifications, sensors, AI, etc.)
• You need the exact methods, properties, events, or enumeration values of a type before writing code
• You're unsure which control, class, or interface to use for a UI or system task

Prerequisites

• .NET SDK 8.0 or later — required to build the cache generator. Install from dotnet.microsoft.com if not available.

Cache Setup (Required Before First Use)

All query and search commands read from a local JSON cache. You must generate the cache before running any queries.

# All projects in the repo (recommended for first run)
.\.github\skills\winmd-api-search\scripts\Update-WinMdCache.ps1

# Single project
.\.github\skills\winmd-api-search\scripts\Update-WinMdCache.ps1 -ProjectDir <project-folder>

No project restore or build is needed for baseline coverage (Platform SDK + WinAppSDK). For additional NuGet packages, the project needs dotnet restore (which generates project.assets.json) or a packages.config file.

Cache is stored at Generated Files\winmd-cache\, deduplicated per-package+version.

What gets indexed

| Source | When available |

|--------|----------------|

| Windows Platform SDK | Always (reads from local SDK install) |

| WinAppSDK (latest) | Always (bundled as baseline in cache generator) |

| WinAppSDK Runtime | When installed on the system (detected via Get-AppxPackage) |

| Project NuGet packages | After dotnet restore or with packages.config |

| Project-output .winmd | After project build (class libraries that produce WinMD) |

> Note: This cache directory should be in .gitignore — it's generated, not source.

How to Use

Pick the path that matches the situation:

Discover — "I don't know which API to use"

The user describes a capability in their own words. You need to find the right API.

0. Ensure the cache exists

If the cache hasn't been generated yet, run Update-WinMdCache.ps1 first — see Cache Setup above.

1. Translate user language → search keywords

Map the user's daily language to programming terms. Try multiple variations:

| User says | Search keywords to try (in order) |

|-----------|-----------------------------------|

| "take a picture" | camera, capture, photo, MediaCapture |

| "load from disk" | file open, picker, FileOpen, StorageFile |

| "describe what's in it" | image description, Vision, Recognition |

| "show a popup" | dialog, flyout, popup, ContentDialog |

| "drag and drop" | drag, drop, DragDrop |

| "save settings" | settings, ApplicationData, LocalSettings |

Start with simple everyday words. If results are weak or irrelevant, try the more technical variation.

2. Run searches

.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action search -Query "<keyword>"

This returns ranked namespaces with top matching types and the JSON file path.

If results have low scores (below 60) or are irrelevant, fall back to searching online documentation:

• Use web search to find the right API on Microsoft Learn, for example:
• site:learn.microsoft.com/uwp/api <capability keywords> for Windows.* APIs
• site:learn.microsoft.com/windows/windows-app-sdk/api/winrt <capability keywords> for Microsoft.* WinAppSDK APIs
• Read the documentation pages to identify which type matches the user's requirement.
• Once you know the type name, come back and use -Action members or -Action enums to get the exact local signatures.

3. Read the JSON to choose the right API

Read the file at the path(s) from the top results. The JSON has all types in that namespace — full members, signatures, parameters, return types, enumeration values.

Read and decide which types and members fit the user's requirement.

4. Look up official documentation for context

The cache contains only signatures — no descriptions or usage guidance. For explanations, examples, and remarks, look up the type on Microsoft Learn:

| Namespace prefix | Documentation base URL |

|-----------------|----------------------|

| Windows.* | https://learn.microsoft.com/uwp/api/{fully.qualified.typename} |

| Microsoft.* (WinAppSDK) | https://learn.microsoft.com/windows/windows-app-sdk/api/winrt/{fully.qualified.typename} |

For example, Microsoft.UI.Xaml.Controls.NavigationView maps to:

https://learn.microsoft.com/windows/windows-app-sdk/api/winrt/microsoft.ui.xaml.controls.navigationview

5. Use the API knowledge to answer or write code

Lookup — "I know the API, show me the details"

You already know (or suspect) the type or namespace name. Go direct:

# Get all members of a known type
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action members -TypeName "Microsoft.UI.Xaml.Controls.NavigationView"

# Get enum values
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action enums -TypeName "Microsoft.UI.Xaml.Visibility"

# List all types in a namespace
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action types -Namespace "Microsoft.UI.Xaml.Controls"

# Browse namespaces
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action namespaces -Filter "Microsoft.UI"

If you need full detail beyond what -Action members shows, use -Action search to get the JSON file path, then read the JSON file directly.

Other Commands

# List cached projects
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action projects

# List packages for a project
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action packages

# Show stats
.\.github\skills\winmd-api-search\scripts\Invoke-WinMdQuery.ps1 -Action stats

> If only one project is cached, -Project is auto-selected.

> If multiple projects exist, add -Project <name> (use -Action projects to see available names).

> In scan mode, manifest names include a short hash suffix to avoid collisions; you can pass the base project name without the suffix if it's unambiguous.

Search Scoring

The search ranks type names and member names against your query:

| Score | Match type | Example |

|-------|-----------|---------|

| 100 | Exact name | Button → Button |

| 80 | Starts with | Navigation → NavigationView |

| 60 | Contains | Dialog → ContentDialog |

| 50 | PascalCase initials | ASB → AutoSuggestBox |

| 40 | Multi-keyword AND | navigation item → NavigationViewItem |

| 20 | Fuzzy character match | NavVw → NavigationView |

Results are grouped by namespace. Higher-scored namespaces appear first.

Troubleshooting

| Issue | Fix |

|-------|-----|

| "Cache not found" | Run Update-WinMdCache.ps1 |

| "Multiple projects cached" | Add -Project <name> |

| "Namespace not found" | Use -Action namespaces to list available ones |

| "Type not found" | Use fully qualified name (e.g., Microsoft.UI.Xaml.Controls.Button) |

| Stale after NuGet update | Re-run Update-WinMdCache.ps1 |

| Cache in git history | Add Generated Files/ to .gitignore |

References

• Windows Platform SDK API reference — documentation for Windows.* namespaces
• Windows App SDK API reference — documentation for Microsoft.* WinAppSDK namespaces