AI Engineer Notebooks: free, framework-free RAG, agents, and evals on Colab

A collection of Jupyter notebooks covering RAG, agent design, and LLM evaluation has been published on GitHub and is free to run on Google Colab. The notebooks are designed to be framework-agnostic, avoiding LangChain and similar abstractions in favor of direct API calls. The series targets working engineers who want practical implementations rather than tutorial-level introductions.