Lesson 5 · 13 min
Build a tiny end-to-end RAG
Put it together: chunks, vectors, retrieval, prompt assembly. All in 50 lines of JavaScript.
The smallest possible RAG
Below is a complete RAG pipeline running locally. Toy embeddings stand in for real ones, but every step is real:
- Document → sentence chunks
- Chunk → vector
- Query → vector
- Cosine similarity → top-k
- Stuff into prompt template
The LLM call is mocked at the end (we don't want to require a key). Plug in a real call where indicated.