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Module 06 · Knowledge

Retrieval, memory and fine-tuning

Information, state and behavior are different problems.

What you’ll learn

Four ideas, one module

01

Three different problems

Information, state and behavior each need a different mechanism.

02

Semantic search

Embeddings, vector similarity and chunking, without the math.

03

RAG and grounding

Find the right text, then answer from it, with sources.

04

Memory and fine-tuning

Where state should live, and when to change the model itself.

Applied exercise

Choose the mechanism

Choose prompt, retrieval, memory, database, fine-tuning—or a combination—for five product scenarios.

  • Documents and policies
  • Users and live data
  • Behavior and style

Cheat sheet

Before choosing a mechanism, ask: is this information, state or behavior?

One page you keep: the questions to ask on every project, the rules of thumb, and a decision guide you can use on your own product. All ten come with The Book.

Leave at the door

Five myths this module breaks

MythWhat’s actually true
“Fine-tuning teaches it our documents.”It shifts behavior. Retrieval supplies the facts.
“RAG stops hallucinations.”Only if retrieval finds the right, current text.
“The vector database is the memory.”It’s one store. Memory is what you choose to keep.
“Similar means relevant.”Close in meaning can still be wrong or outdated.
“Big context windows kill retrieval.”Cost, latency and access still favor selecting.

Before you move on

Can you call this one?

A sales bot quotes old prices, forgets clients and sounds off-brand.

Split it into information, state and behavior. Which mechanism fixes each?

Portrait of Nika Soren

The Memory Architect

Nika Soren

explores how AI systems retrieve, retain and adapt knowledge, and why remembering is not the same as learning.

Episode 06 · Retrieval, memory and fine-tuning

Included with the course.

Coming soon · an AI character from the show, not a real researcher.