Skip to specification

The model never remembers. Something around it does.

Spend a week with a coding agent and it feels like it knows you. But when the context window closes, the weights don’t change. A memory architecture stored that information, pulled it back at the right moment, and fed it into the next prompt.

filing cabinet → context builder → the desk · click to inspect

8 parts · every selection is linkable
FIG. 1 — the memory architecture. Durable stores at left, the context builder in the middle, the desk at right. Click any part to inspect it.

The chain of limitations — 6 sheets

  1. 01Working MemoryThe active context the model can see right now — the desk. Every token in the prompt is active state, and it runs on a budget.

    Working memory breaks two ways: it ends when the session ends, and it fills up. Nothing survives the boundary on its own.

  2. 02Episodic MemoryWhat the agent remembers happening — a specific investigation, a specific debugging session. The key property: it has a when.

    The past session says what happened last time. It cannot say what is true right now — or whether last time still holds.

  3. 03Semantic MemoryStanding facts that float free of time: repo layout, project rules, user preferences, name-to-ID mappings. The agent just knows.

    Facts go stale and contradict. Without conflict handling, an old truth sits next to a new one as an equal — and memory becomes friction.

  4. 04Procedural MemoryThe how-to layer: runbooks, checklists, skills, tool schemas, orchestration code. Knowing how to ride the bike, not just that it has two wheels.

    Durable stores are just a filing cabinet. None of it matters until the right slice reaches the context window at the right moment.

  5. 05Context AssemblyThe engineering problem at the heart of memory: retrieve, rank, and assemble slices of every store into the working context. The model only ever works at the desk.

    A system that remembers everything eventually remembers too much. Perfect recall with no forgetting is the coworker who reads out their entire diary.

  6. 06Forgetting & ConflictsMemory hygiene: temporal decay, contradiction handling, compression, manual curation. Old memories can stay — they just shouldn't outrank what's true.

    If you can answer the five questions — what's in working memory, which session matters, which facts are current, which workflow applies, what should be forgotten — you have an architecture. If not, you have scattered state.

Four kinds of remembering

Borrowed from cognitive science, and mapped one-to-one onto agent systems. Hover to see what each one holds.