LLM Function Calling: Connect AI to APIs and Databases

Large Language Models are powerful, but they become truly transformative when they can interact with the outside world. If you want to move beyond simple text generation and build applications that can fetch real-time data, execute actions, and query databases, you need to understand function calling. This course teaches you how to connect LLMs to external APIs and services using modern tool use techniques. You will learn the foundational concepts of AI application development, enabling you to design intelligent workflows that can read, process, and act upon external data securely. What you will learn: • Understand the foundational concepts of LLMs, function calling, and AI agents • Design and format system prompts to reliably trigger external tools • Connect language models to external REST APIs to fetch real-time data • Apply fundamental Retrieval-Augmented Generation (RAG) patterns to interact with databases • Structure and parse JSON payloads securely between the model and your backend • Build text-based AI workflows that chain multiple functions together The course begins with essential AI terminology and basic prompt engineering before moving into practical, written exercises on structuring function calls. You will progress through step-by-step text tutorials that explain how to integrate language models with various backend services. This course is designed for beginners and aspiring developers who want to learn AI integration from the ground up, with no prior machine learning experience required. Start reading today to unlock the power of LLM tool use and build your first intelligent backend integration.