AlejandrIA
Fundamentos Teóricos de LLMs

Version history

What's new

This book is updated in editions, not silently. Here's what changed between them, and how to open whichever version you want.

Edition 2

current 2026

Structure and languages

  • The book is now trilingual: a complete new English edition, alongside Portuguese and Spanish.
  • Restructured from 14 to 16 modules: Prompt and Context Engineering, RAG and GraphRAG, AI Agents, and Integration and Interoperability are now their own chapters, instead of parts of a larger module.

Deeper content

  • All 16 modules were rewritten with deeper theoretical coverage (the text grew from roughly 57,000 to 78,000 words).
  • New section on tacit knowledge, explicit knowledge, and the role of ontologies in sectors with rigorous technical criteria (Module 14).
  • Real cases added: the ELIZA effect, the Mata v. Avianca court case, Air Canada's chatbot, and the car sold for US$ 1 by a misconfigured chatbot.
  • "In Practice" sections in every module, with free, reproducible experiments (Teachable Machine, TensorFlow Playground, Transformer Explainer, Hugging Face, Gandalf, among others).

Figures and visual resources

  • Dozens of new original technical figures, including interactive comparisons (click to switch) between a base model, an instruction-tuned model, and an RLHF-aligned model.
  • New visual decision guides: when to use RAG vs. GraphRAG, when to trust, verify, or intervene with an agent, and more.

References and glossary

  • Expanded bibliography, with more than twenty new academic references.
  • Glossary nearly doubled, with terms remapped by module.

Edition 1

archived 2026
  • The book's initial release: 14 modules, in Portuguese and Spanish.
  • Full coverage of LLM fundamentals, from tokens and attention to RAG, agents, and security.

Edition 1 remains published, unchanged, for anyone already using it or who prefers the original structure.