using System;using System.Text.Json;using Agent.Core.ToolCalling;​namespace Agent.Addons.Tools;​/// <summary>Addon tool — changes the text-to-speech (TTS) voice.</summary>public static class ChangeVoiceTool{    public const string Name = "change_voice";​    public static void Register(ToolRegistry registry)    {        registry.Register(new AgentTool(            Name,            "Changes the text-to-speech (TTS) voice. Available voices include: af_heart, af_bella, af_sarah, af_nicole, af_sky, am_adam, am_michael, bf_emma, bf_isabella, bm_george, bm_lewis.",            args => Invoke(registry, args),            ParametersSchema,            ToolCategory.Addon));    }​    private static object ParametersSchema => new    {        type = "object",        properties = new        {            voice = new { type = "string", description = "The voice ID to switch to, e.g., 'af_bella' or 'bf_emma'." }        },        required = new[] { "voice" }    };​    private static string Invoke(ToolRegistry registry, string argumentsJson)    {        string voice = ParseVoice(argumentsJson);        if (string.IsNullOrWhiteSpace(voice))        {            return "Error: Provide a voice ID (JSON property \"voice\").";        }​        try        {            registry.InvokeVoiceChanged(voice);            return $"Success: TTS voice changed to '{voice}'.";        }        catch (Exception ex)        {            return $"Error changing voice: {ex.Message}";        }    }​    private static string ParseVoice(string argumentsJson)    {        try        {            using var doc = JsonDocument.Parse(argumentsJson);            if (doc.RootElement.TryGetProperty("voice", out var voiceProp))            {                return voiceProp.GetString()?.Trim() ?? "";            }        }        catch (JsonException)        {            // fall through        }​        return "";    }}​