Icon

You can display an icon, based on a font glyph, using the Icon(string, char) static method, which produces a IUIIcon.

See Create custom icon to learn how to create a custom font and add it to your extension.

Sample

using DevToys.Api;
using System.ComponentModel.Composition;
using static DevToys.Api.GUI;

namespace MyProject;

[Export(typeof(IGuiTool))]
[Name("My Tool")]
[ToolDisplayInformation(
    IconFontName = "FluentSystemIcons",
    IconGlyph = '\uE670',
    ResourceManagerAssemblyIdentifier = nameof(MyResourceAssemblyIdentifier),
    ResourceManagerBaseName = "MyProject.Strings",
    ShortDisplayTitleResourceName = nameof(Strings.ShortDisplayTitle),
    DescriptionResourceName = nameof(Strings.Description),
    GroupName = "My Group")]
internal sealed class MyGuiTool : IGuiTool
{
    public UIToolView View
        => new UIToolView(
            Icon("FluentSystemIcons", '\uE670')
                .Size(48));

    public void OnDataReceived(string dataTypeName, object? parsedData)
    {
        // Handle Smart Detection.
    }
}

The code above produces the following UI: