AgentKit Node SDK

The official Node.js SDK for AgentKit.

AgentKit lets you expose your existing backend functions as AI-callable tools without rewriting your application or exposing public endpoints.

Features

• 🚀 Register existing backend functions as AI tools
• 🔒 Outbound-only WebSocket connection (no public endpoints required)
• 📦 TypeScript-first
• ✅ Supports Zod and JSON Schema
• ⚡ Automatic reconnection
• ❤️ Works with Express, NestJS, Fastify and any Node.js server

Installation

npm install @rutvikmakvana/agentkit-node

Quick Start

import { agentkit } from "@rutvikmakvana/agentkit-node";
import { z } from "zod";

agentkit.init({
  projectKey: process.env.AGENTKIT_PROJECT_KEY!,
});

agentkit.tool({
  name: "getOrder",
  description: "Get order details by ID",
  input: z.object({
    orderId: z.string(),
  }),
  handler: async ({ orderId }) => {
    return orderService.getOrder(orderId);
  },
});

agentkit.connect();

API

Initialize

agentkit.init({
  projectKey: "...",
});

Register Tool

agentkit.tool({
  name,
  description,
  input,
  handler,
});

Connect

agentkit.connect();

Disconnect

agentkit.disconnect();

Supported Schemas

Zod

input: z.object({
  id: z.string(),
});

JSON Schema

input: {
  type: "object",
  properties: {
    id: {
      type: "string"
    }
  }
}

Events

agentkit.on("connected", ...);

agentkit.on("disconnected", ...);

agentkit.on("toolCalled", ...);

agentkit.on("error", ...);

Supported Frameworks

• Express
• NestJS
• Fastify
• Hono
• Koa
• Any Node.js HTTP server

How AgentKit Works

Your Backend
      │
      │
agentkit.connect()
      │
      ▼
Outbound WebSocket
      │
      ▼
AgentKit Cloud
      │
      ▼
LLM invokes your tool
      │
      ▼
Your existing function executes
      │
      ▼
Response returned to the AI

No public API endpoints.

No ngrok.

No inbound ports.

Works locally and in production.

Requirements

• Node.js 18+
• TypeScript 5+

License

MIT