Maui Platform Invoke

What it does

When your agent uses it

• : platform-specific code
• Conditional compilation
• Multi-targeting
• Native API call

Example prompts

• “platform-specific code”
• “conditional compilation”
• “partial class”
• “/maui-platform-invoke”

Workflow steps

4 steps, taken from the step headings in SKILL.md.

1. 1Overusing #if directives
2. 2Mismatched namespaces in partial classes
3. 3Depending on concrete classes in shared code
4. 4Forgetting the #else fallback

What it can do on your machine

Read from SKILL.md and the folder at commit 79bb4bf. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are csharp).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Maui Platform Invoke loads about 1.1k tokens when it runs, and up to ~2.1k if it reads all its reference files. Until then it costs about 171 tokens; SKILL.md has 234 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~171

When it runs · the whole SKILL.md, loaded when a task matches

~1.1k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~2.1k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from davidortinau/maui-skills at commit 79bb4bf, republished under its MIT licence (© davidortinau). 234 words, ~1,099 tokens.

name

maui-platform-invoke

description

Guidance for calling platform-specific native APIs from .NET MAUI apps. Covers partial classes, conditional compilation, multi-targeting configuration, and dependency injection patterns for cross-platform code that needs Android, iOS, Mac Catalyst, or Windows functionality. USE FOR: "platform-specific code", "conditional compilation", "partial class", "#if ANDROID", "#if IOS", "multi-targeting", "native API call", "platform invoke", "platform-specific DI", "DeviceInfo.Platform". DO NOT USE FOR: custom control handlers (use maui-custom-handlers), permission requests (use maui-permissions), or dependency injection patterns (use maui-dependency-injection).

// ❌ Complex logic buried in #if blocks — untestable, hard to read
public async Task<bool> CheckConnectivity()
{
#if ANDROID
    // 30 lines of Android networking code...
#elif IOS
    // 25 lines of iOS networking code...
#endif
}

// ✅ Use partial classes — each platform file is clean and testable
// Services/ConnectivityService.cs (shared)
public partial class ConnectivityService
{
    public partial Task<bool> CheckConnectivityAsync();
}
// Platforms/Android/Services/ConnectivityService.cs
public partial class ConnectivityService
{
    public partial Task<bool> CheckConnectivityAsync() { /* Android impl */ }
}

// ❌ Different namespaces — creates TWO unrelated classes
// Services/MyService.cs
namespace MyApp.Services;
public partial class MyService { }

// Platforms/Android/MyService.cs
namespace MyApp.Platforms.Android;  // WRONG!
public partial class MyService { }

// ✅ Same namespace everywhere
namespace MyApp.Services;
public partial class MyService { }

// ❌ Shared code depends on concrete platform type — can't mock in tests
public class MyViewModel
{
    readonly DeviceOrientationService _service = new();
}

// ✅ Depend on interface — enables unit testing and swapping
public class MyViewModel
{
    readonly IDeviceOrientationService _service;
    public MyViewModel(IDeviceOrientationService service) => _service = service;
}

// ❌ Fails compilation on unsupported platforms
public string GetDeviceName()
{
#if ANDROID
    return Android.OS.Build.Model;
#elif IOS
    return UIKit.UIDevice.CurrentDevice.Name;
#endif  // No return for Windows or other platforms!
}

// ✅ Always include a fallback
#else
    return "Unknown";
#endif

© davidortinau, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (references) in plugins/maui-skills/skills/maui-platform-invoke of davidortinau/maui-skills.

• SKILL.md
• references/platform-invoke-api.md

Open the folder on GitHubat commit 79bb4bf