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name: customerio-install-auth description: | Install and configure Customer.io SDK/CLI authentication. Use when setting up a new Customer.io integration, configuring API keys, or initializing Customer.io in your project. Trigger with phrases like "install customer.io", "setup customer.io", "customer.io auth", "configure customer.io API key". allowed-tools: Read, Write, Edit, Bash(npm:), Bash(pip:), Grep version: 1.0.0 license: MIT author: Jeremy Longshore jeremy@intentsolutions.io

Customer.io Install & Auth

Overview

Set up Customer.io SDK and configure authentication credentials for email, push, SMS, and in-app messaging automation.

Prerequisites

• Node.js 18+ or Python 3.10+
• Package manager (npm, pnpm, or pip)
• Customer.io account with API access
• Site ID and API Key from Customer.io dashboard

Instructions

Step 1: Install SDK

# Node.js (Track API)
npm install customerio-node

# Node.js (Journeys Track API - recommended)
npm install @customerio/track

# Python
pip install customerio

Step 2: Configure Authentication

# Set environment variables
export CUSTOMERIO_SITE_ID="your-site-id"
export CUSTOMERIO_API_KEY="your-api-key"

# Or create .env file
cat >> .env << 'EOF'
CUSTOMERIO_SITE_ID=your-site-id
CUSTOMERIO_API_KEY=your-api-key
EOF

Step 3: Verify Connection

import { TrackClient, RegionUS } from '@customerio/track';

const client = new TrackClient(
  process.env.CUSTOMERIO_SITE_ID,
  process.env.CUSTOMERIO_API_KEY,
  { region: RegionUS }
);

// Test by identifying a user
await client.identify('test-user', { email: 'test@example.com' });
console.log('Customer.io connection successful');

Output

• Installed SDK package in node_modules or site-packages
• Environment variables or .env file with Site ID and API Key
• Successful connection verification output

Error Handling

Error	Cause	Solution
Invalid API Key	Incorrect or expired key	Verify key in Customer.io Settings > API Credentials
Invalid Site ID	Wrong site identifier	Check Site ID in Customer.io Settings
401 Unauthorized	Authentication failed	Ensure both Site ID and API Key are correct
Network Error	Firewall blocking	Ensure outbound HTTPS to track.customer.io allowed
Module Not Found	Installation failed	Run npm install or pip install again

Examples

TypeScript Setup

import { TrackClient, RegionUS, RegionEU } from '@customerio/track';

// US region (default)
const client = new TrackClient(
  process.env.CUSTOMERIO_SITE_ID!,
  process.env.CUSTOMERIO_API_KEY!,
  { region: RegionUS }
);

// EU region
const euClient = new TrackClient(
  process.env.CUSTOMERIO_SITE_ID!,
  process.env.CUSTOMERIO_API_KEY!,
  { region: RegionEU }
);

Python Setup

import os
from customerio import CustomerIO

cio = CustomerIO(
    site_id=os.environ.get('CUSTOMERIO_SITE_ID'),
    api_key=os.environ.get('CUSTOMERIO_API_KEY')
)

Resources

• Customer.io Documentation
• Track API Reference
• Customer.io Status

Next Steps

After successful auth, proceed to customerio-hello-world for your first API call.