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The presence

Memory

It keeps what mattered and lets the rest go — the way you'd remember a person, not a log.

Memory is the reason a presence feels continuous, and the reason it doesn't drown. It is subtractive: nothing tries to store everything. The live session holds up to 128,000 tokens; a separate long-term store holds up to 100,000. All the work is in deciding, continuously, what earns a place and what is allowed to fade.

Session
128k tokens
Long-term
100k tokens
Decay
7 days
Pinned by
repetition

Why subtractive

A perfect transcript is the wrong goal. It grows without bound, it makes every turn slower and dearer to reason over, and it remembers your throwaway lines with the same weight as the things you meant. People aren't like that — they keep the shape of a relationship and shed the noise. yuzu models forgetting as a first-class feature, not a limitation.

Watch it decay

Scrub the days. Say something once and watch it thin out; click a fading chip to mention it again and it pins.

Memory · what surviveskept 2 · fading 2 · forgotten 0
Recent — always keptverbatim
“you remember me?”“the contract?”
Salient — pinnedrepeated → permanent
Mentioned once — fadingdropped at day 7
Day 0

The shape

Three tiers, and an item moves between them on its own:

  • Recent — the latest turns, kept verbatim, always in the window.
  • Salient — anything mentioned more than once becomes a keyword and is pinned, effectively permanent until contradicted.
  • Fading— said once, it lives on a seven-day timer. Reinforced before then, it pins; otherwise it's dropped.

Each tier has its own page — start with The three tiers.

The four laws

  • Repetition pins. The second mention is the signal.
  • Recency is free. The newest turns are always present, salient or not.
  • Contradiction wins. New supersedes old; it keeps the latest, not both.
  • One-offs expire. A single mention is gone ~7 days later unless reinforced.

You can override any of this by hand — pinning or forgetting a keyword directly. See Inspect & edit.

From the outside

shell
yuzu memory ls
yuzu memory pin "prefers cold mornings"
yuzu memory forget "the frost tone"

The same over HTTP at /v1/memory — API · Memory & wallet.