Application service as a tool

using ModelContextProtocol.Server;
using Runiq.AI.Mcp;
using System.ComponentModel;

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddScoped<TextLengthService>();
builder.Services.AddRuniqMcp();

var app = builder.Build();
app.MapRuniqMcp();
app.Run();

/// <summary>Calculates text length for the application.</summary>
public sealed class TextLengthService
{
    /// <summary>Returns the UTF-16 code unit count.</summary>
    public int Count(string text)
    {
        ArgumentNullException.ThrowIfNull(text);
        return text.Length;
    }
}

/// <summary>Exposes text inspection through MCP.</summary>
[McpServerToolType]
public sealed class TextLengthMcpTool
{
    private readonly TextLengthService service;

    /// <summary>Creates an adapter for the text service.</summary>
    public TextLengthMcpTool(TextLengthService service)
    {
        this.service = service;
    }

    /// <summary>Returns the UTF-16 length of the supplied text.</summary>
    [McpServerTool(Name = "text_length")]
    [Description("Returns the number of UTF-16 code units in the supplied text.")]
    public int Count(
        [Description("The text to measure.")] string text)
    {
        return service.Count(text);
    }
}