Langfuse Install & Auth Overview Install the Langfuse SDK and configure authentication for LLM observability. Covers both the legacy package (v3) and the modern modular SDK (v4+/v5) built on OpenTelemetry. Prerequisites - Node.js 18+ or Python 3.9+ - Package manager (npm, pnpm, or pip) - Langfuse account (cloud at https://cloud.langfuse.com or self-hosted) - Public Key ( ) and Secret Key ( ) from project settings Instructions Step 1: Install SDK TypeScript/JavaScript (v4+ modular SDK -- recommended): TypeScript/JavaScript (v3 legacy -- single package): Python: Step 2: Get API Keys 1. Open Lan…