The TL;DR If you need to spin up a local, privacy-first AI agent that can query your own internal documents without sending data to third-party APIs, this guide covers the exact architecture using TypeScript, Python, and Ollama. Time to complete: ~15 minutes. Prerequisites: Python 3.10+ or Node.js installed, basic familiarity with embeddings. The Problem: API Costs & Data Privacy When building production-ready LLM features, relying solely on cloud providers introduces two major friction points: