Quick start

Install the CLI

npm install -g @jelou/cli

Verify the installation:

jelou --version

Authenticate

You need a personal access token (create one in the Jelou dashboard).

jelou login
# Paste your access token: ****
# ✓ Logged in

In CI you can pass the token directly: jelou login --token jfn_pat_your_token

Initialize a project

Create a directory and run jelou functions init:

mkdir query-customer && cd query-customer
jelou functions init
# ? Function slug: query-customer
# ? Description: Looks up customer information for the WhatsApp channel
# ? Create new or link existing? Create new
# ✓ Created query-customer

This generates the base files:

File	Purpose
`index.ts`	Your main function
`jelou.json`	Project configuration
`deno.json`	SDK import map
`.env`	Local environment variables

Write your function

Replace the contents of index.ts with a function that looks up customers by phone:

index.ts

import { define, z } from "@jelou/functions";

export default define({
  name: "query-customer",
  description: "Looks up customer information by phone number for the support channel",
  input: z.object({
    phone: z.string().min(10).describe("Customer phone number"),
  }),
  output: z.object({
    name: z.string(),
    email: z.string(),
    plan: z.string(),
    balance: z.number(),
  }),
  handler: async (input, ctx) => {
    ctx.log("Looking up customer", {
      phone: input.phone,
      company: ctx.company.id,
    });

    const apiKey = ctx.env.get("CRM_API_KEY");
    const res = await fetch(
      `https://crm.example.com/api/customers?tel=${input.phone}`,
      { headers: { Authorization: `Bearer ${apiKey}` } },
    );
    const customer = await res.json();

    return {
      name: customer.name,
      email: customer.email,
      plan: customer.plan,
      balance: customer.balance,
    };
  },
});

Run locally

Start the development server:

jelou functions dev
# ▸ Listening on http://localhost:3000
# ▸ Watching for changes...

Your server reloads automatically when you edit files.

Test with curl

In another terminal, send a request:

curl -X POST http://localhost:3000 \
  -H "Content-Type: application/json" \
  -d '{"phone": "593987654321"}'

Response:

{
  "name": "Maria Garcia",
  "email": "[email protected]",
  "plan": "Premium",
  "balance": 150.00
}

You can also test the MCP endpoint at http://localhost:3000/mcp and the health check at http://localhost:3000/__health.

Configure secrets

Before deploying, add the environment variables your function needs:

jelou functions secrets set query-customer CRM_API_KEY=YOUR_CRM_API_KEY
# ✓ Set 1 secret

Deploy to production

jelou functions deploy
# ▸ Files: index.ts (1.2 KB), jelou.json (98 B), deno.json (65 B)
# ? Deploy query-customer? (Y/n) y
# ✓ Deployed to https://query-customer.fn.jelou.ai

Your function is protected by default. To call it you need a platform API key — create one at apps.jelou.ai, in the app configuration section, and send it as Authorization: Bearer sk_.... See the authentication guide for details.

Your function is now available in production. Jelou AI agents can invoke it as an MCP tool automatically.

Verify in production

curl -X POST https://query-customer.fn.jelou.ai \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sk_..." \
  -d '{"phone": "593987654321"}'

Monitor logs in real time:

jelou functions logs query-customer

Next steps

Input/output validation — Zod schemas, type coercion, and error format
Multi-tool functions — group multiple tools in a single deployment with app()

Getting Started

Developer

Jelou CLI

Outbound Messaging

Management

Marketplace

Channels

Configuration

Billing

Next steps

​Next steps

Next steps