Tools

Built-in tools

BuiltInTools.Safe is the default safe set. BuiltInTools.All includes the larger built-in inventory.

The built-in catalog covers file operations, shell execution, web fetch and search, memory, base64 helpers, task management, and interactive prompts.

Attribute-based tools

Use [Tool] and [ToolParam] for strongly typed registration:

[Tool("add", "Add two numbers")]
public static ToolResult Add(
    IToolContext context,
    [ToolParam("First number")] double a,
    [ToolParam("Second number")] double b)
{
    return ToolResult.Success($"{a} + {b} = {a + b}");
}

Register tools with:

• Tool.FromType<T>()
• Tool.FromMethod<T>(...)
• Tool.FromInstance(...)

Fluent tool builder

For dynamic tool definitions, use Tool.Create(...):

var tool = Tool.Create("custom_tool")
    .WithDescription("A custom tool created with the builder pattern")
    .WithParameter<string>("input", "Input text to process")
    .WithHandler(async (parameters, context) =>
    {
        var input = parameters["input"]?.ToString() ?? "";
        return ToolResult.Success(input.ToUpperInvariant());
    })
    .Build();

MCP integration

Document MCP using the verified APIs:

• Agent.McpServers
• McpToolLoader.LoadAsync(...)
• McpToolLoader.DiscoverAsync(...)

Avoid older sample text that implies BuiltInTools.FromMcpServerAsync(...) is the supported path.