Klaviyo Install & Auth Overview Set up the official Node.js SDK and configure private API key authentication against Klaviyo's REST API (revision ). Prerequisites - Node.js 18+ (or Python 3.10+ for Python SDK) - Klaviyo account at https://www.klaviyo.com/ - Private API key from Settings API Keys in Klaviyo dashboard - Public API key (for client-side only -- never use in server code) Instructions Step 1: Install the Official SDK Important: The npm package is , not . The SDK exports per-resource API classes (ProfilesApi, EventsApi, etc.) that each take an . Step 2: Configure Authentication Klav…