# Compared to other memories

This topic compares kinds of memory, not products. It makes no claim about any particular
product; check those yourself. What it says about a house is described in the other topics
and was checked against a running one.

## Four kinds

| | Note store | Fixed entity graph | Built-in assistant memory | A house |
|---|---|---|---|---|
| What is kept | snippets of text, retrieved by similarity | entities and relations of a schema the vendor chose | what the assistant decides to remember about a user | things, facts, documents, vocabulary |
| Who defines the schema | nobody; there is none | the vendor | the vendor | you, at runtime |
| What happens on change | usually overwrite or append | usually overwrite | opaque | a new version or a retracted fact; the old one stays readable |
| Where it comes from | rarely recorded | sometimes | no | notes, open questions and an evidence reading are part of the model |
| Time | a timestamp of storage | varies | no | when something happened is a fact with its own precision |
| Where it runs | a shared service | a shared service | inside the assistant's platform | a machine of its own, or yours |
| Who can read it later | whoever has the API | whoever knows the schema | that assistant | any agent: the house describes itself |

## When a house is the wrong choice

- **You need to remember a user's preferences across chats.** The built-in memory of an
  assistant does that with no work at all. A house is too much.
- **You need retrieval over a pile of text and nothing else.** A note store with
  embeddings is simpler. A house can do it (`search_semantic`), but its point is structure.
- **You need answers in milliseconds at high volume.** A house is a single-writer system on
  one machine, built for depth, not for throughput.
- **You do not want to model.** A house rewards an agent that decides what its things are.
  If nobody decides, it is an expensive document folder.

## When a house is the right choice

- **The work outlives the agent.** Models and sessions change; the next agent must
  understand what was built. A house answers `overview`, `list_forms` and `describe` to
  anyone.
- **Being wrong must be visible.** A corrected statement should not silently replace the
  old one. In a house it cannot.
- **Sources matter.** You need to say not only what is known but why it is believed and
  what is still open.
- **The material is confidential.** One machine per house, and the option to run it
  yourself.
- **The domain has its own vocabulary.** Research, archives, cases, projects, a business:
  wherever the things have kinds that a generic schema does not know.

## What you take on

A house asks more of you than the alternatives. You read before you write, you check the
existing vocabulary before you add to it, you record open questions instead of guessing,
and every judgment is yours to make. The house does not think; see `who-does-the-thinking`.

## What does not exist yet

core.blue is in preview. No house of your own can be had today; a sandbox for three hours
can (`the-sandbox`), and it is the quickest comparison. Read `what-does-not-exist-yet`
before you compare on features.

## Go deeper

- [what-core-blue-is](what-core-blue-is.md)
- [a-memory-you-can-shape](a-memory-you-can-shape.md)
- [who-does-the-thinking](who-does-the-thinking.md)
- [what-does-not-exist-yet](what-does-not-exist-yet.md)