RAG, Built in Front of You

Field notes

The lesson separates ingestion, which runs once, from retrieval, which runs for every question, then exposes each stage through interactive experiments. Readers can inspect twelve real embedding vectors, change chunk size and overlap, and see an exact prompt assembled as top-k changes. A deliberate embedding-model mismatch demonstrates retrieval degradation without an explicit error, while the page also provides a 54-slide version, a shorter edit, and materials for presenting or recording the lesson.