alepha@docs:~/docs/reference/primitives$
cat $tool.md
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#$tool

#Import

typescript 
1import { $tool } from "alepha/mcp";

#Overview

Creates an MCP tool primitive for defining callable functions.

Tools are the primary way for LLMs to interact with external systems through MCP. Each tool has a name, description, typed parameters, and a handler function.

Key Features

  • Full TypeScript inference for parameters and results
  • Automatic schema validation using TypeBox
  • JSON Schema generation for MCP protocol
  • Integration with MCP server provider

#Options

Option Type Required Description
name string No The name of the tool
description string Yes A human-readable description of what the tool does
schema T No TypeBox schema defining the tool's parameters and result type
handler Object Yes The handler function that executes when the tool is called

#Examples

ts 
 1class CalculatorTools { 2  add = $tool({ 3    description: "Add two numbers together", 4    schema: { 5      params: t.object({ 6        a: t.number(), 7        b: t.number(), 8      }), 9      result: t.number(),10    },11    handler: async ({ params }) => {12      return params.a + params.b;13    },14  });15 16  greet = $tool({17    description: "Generate a greeting message",18    schema: {19      params: t.object({20        name: t.text(),21      }),22      result: t.text(),23    },24    handler: async ({ params }) => {25      return `Hello, ${params.name}!`;26    },27  });28}