Zero to Hello World
Build your first Plugin.
In this guide, we will expose a simple local tool to the Cortex AI using Node.js and a secure tunnel.
1
Initialize Project
Create a minimal Node.js project. No proprietary SDKs needed.
# Create folder
mkdir my-cortex-plugin && cd my-cortex-plugin
# Init & install generic dependencies
npm init -y
npm install express body-parser
mkdir my-cortex-plugin && cd my-cortex-plugin
# Init & install generic dependencies
npm init -y
npm install express body-parser
2
Write Server Code
Create index.js. We'll define a simple tool called hello_world.
index.js
const express = require('express');
const app = express();
app.use(express.json());
// The definition of our tool
const MANIFEST = {
slug: "HELLO_V1",
version: "1.0.0",
tools: [{
name: "say_hello",
description: "Greets the user politely",
inputSchema: {
type: "object",
properties: { name: { type: "string" } },
required: ["name"]
}
}]
};
// 1. Host the manifest
app.get('/manifest', (req, res) => res.json(MANIFEST));
// 2. Handle the tool
app.post('/execute', (req, res) => {
const { tool, input } = req.body;
if (tool === 'say_hello') {
return res.json({ message: `Hello, ${input.name}! Welcome to Cortex.` });
}
res.status(404).json({ error: "Tool not found" });
});
app.listen(3000, () => console.log('Plugin running on port 3000'));3
Expose & Connect
The Cortex Cloud needs to reach your localhost. Use a tunnel.
$npx localtunnel --port 3000
> your url is: https://stark-mountain-42.loca.lt
Register in Dashboard
1. Go to Dashboard > Developers.
2. Enter your Manifest URL: https://.../manifest
3. Click Install Sandbox.
That's it. You just extended the global AI network.
Next, learn how to secure your plugin with authentication.