What this is

No new concepts in this lesson. This is a checkpoint: a small, real script built entirely out of ideas from Lessons 1 through 8, combined into one thing. If you can read lesson.py and understand why every piece is there, you've mastered the Beginner tier. If any piece feels unfamiliar, that's a sign to revisit the lesson it came from before continuing to Intermediate.

What it does

Loads every fixture note in lessons/naive_rag/fixtures/notes/ (five short Markdown files about a weather station, a garden, a pizza recipe, a bookshelf, and cello practice), embeds and stores all of them, then answers three questions, each one drawing on a different file, printing the whole run so you can see the pipeline work across more than one document for the first time.

Where each piece came from

def load_documents() -> list[str]:
    return [path.read_text() for path in sorted(NOTES_DIR.glob("*.md"))]

A new twist on Lesson 4's chunking, not a new concept: instead of splitting one long file into chunks, each already-short file is one chunk. sorted(...) keeps the file order consistent across runs (glob alone doesn't guarantee an order).

store = build_vector_store(documents)

Lesson 5, unchanged: embed every chunk in one batched call, pair each with its embedding.

retrieved = retrieve(query, store, k)

Lesson 6, unchanged: embed the question, rank every chunk by cosine similarity, keep the top k.

return generate_answer(query, retrieved)

Lesson 7, unchanged: stuff the retrieved chunks into a prompt, ask Gemini to answer only from that context.

def ask(query: str, store: list[dict], k: int = 2) -> str:
    retrieved = retrieve(query, store, k)
    return generate_answer(query, retrieved)

Lesson 8's ask(), unchanged: the whole pipeline as one function call.

Try this yourself

Without looking anything up:

  • Add a new .md file of your own to fixtures/notes/ (a made-up note about a topic not already covered), does asking about it work correctly on the next run?
  • Change k from 2 to 1 in one of the ask() calls, does the pizza question (which needs the recipe file specifically) still get answered correctly with only the single best match?
  • Ask a question that spans two files at once, for example "What two hobbies happen in the same room as the weather station?" (the answer needs bookshelf.md and cello-practice.md together). Does k=2 retrieve both of the right files, or does it miss one?

If you can make these changes confidently, you're ready for the Intermediate tier, starting at Lesson 10.