Tool calling (Version 3)

using System.Globalization;using System.Text.Json;​namespace Agent.Core.ToolCalling;​/// <summary>Default Agent-Core tools: current local time and date.</summary>public static class BuiltInTools{    public const string GetTimeName = "get_time";    public const string GetDateName = "get_date";    public const string ChangeNameName = "change_name";​    public static void Register(ToolRegistry registry)    {        registry.Register(new AgentTool(            GetTimeName,            "Returns the current local time on this machine.",            _ => DateTime.Now.ToString("T", CultureInfo.CurrentCulture)));​        registry.Register(new AgentTool(            GetDateName,            "Returns today's local date on this machine.",            _ => DateTime.Now.ToString("D", CultureInfo.CurrentCulture)));​        registry.Register(new AgentTool(            ChangeNameName,            "Changes the name of the assistant.",            args => {                string newName = ParseName(args);                if (string.IsNullOrWhiteSpace(newName)) return "Error: name cannot be empty.";                registry.InvokeNameChanged(newName);                return $"Success: Name changed to {newName}.";            },            new {                type = "object",                properties = new {                    name = new { type = "string", description = "The new name for the assistant." }                },                required = new[] { "name" }            }));    }​    private static string ParseName(string argumentsJson)    {        try        {            using var doc = JsonDocument.Parse(argumentsJson);            if (doc.RootElement.TryGetProperty("name", out var nameProp))            {                return nameProp.GetString()?.Trim() ?? "";            }        }        catch (JsonException)        {        }        return "";    }}​