This repository is an educational cookbook from Upstage, centered on their Solar LLM and Document AI APIs. It contains a large collection of Jupyter notebooks (Solar-Fullstack-LLM-101) that teach prompt engineering, RAG, cache-augmented generation, tool calling, and fact-checking with knowledge graphs, plus a Flask sample backend (Bremen) and a Flutter mobile app. The dominant character is a notebook-driven ML/research collection, but it is hybrid because it includes runnable application code (Flask API, Flutter app) and static data assets (OCR JSON, CSV knowledge bases).