01 |SUPERSESSION
The old fact stays. The new one wins. valid_until closes the old value.
A new value sets valid_until on the old one instead of overwriting it, so asking what the agent believed on a given date is one query. The trace plays one correction from write to as-of read.
Session 4 · turn 42
Facts written
Tobie works at Acme as CTO
turn:42 · chars 15-38 · confidence 0.91
Acme is an organisation
turn:42 · chars 34-38 · confidence 0.95
Session 9 · turn 43
Facts after reconciliation
Tobie works at Acme as CTO
superseded · valid_until 2026-04-12 · row retained
Tobie works at SurrealDB
turn:43 · chars 12-30 · confidence 0.88
Ask · today
Where does Tobie work?
SurrealDB
cited turn:43
Ask · as of 2026-04-01
Where does Tobie work?
Acme, as CTO
cited turn:42 · superseded 2026-04-12
02 |WHAT YOU GET
Three clocks. Each one answers a different question.
Supersede, do not overwrite
System time
Known time
Valid time
Forget
Purge
03 |WHY IT MATTERS
What overwriting throws away. What the agent believed, and when.
Visible to the very next read
A new fact is reconciled when it is written, so the very next read sees it and nothing is re-indexed overnight.
Reconciled in code
Which value wins is decided in code, not by a model, and a value scored below the confidence floor never silently replaces a stronger one.
History has a cost
Keeping history means storage grows with it. Purge removes history where erasure is required.
Cached answers step aside
A cached answer is never reused once a fact it cited is superseded, so recall does not serve the old value.
GET STARTED
Give your agents a memory with a history. Facts are superseded rather than overwritten, on three clocks, with purge for erasure.
