Definition
Plain language
When an AI assistant keeps using stale facts because new information didn't properly overwrite the old.
As stated in the literature
In the agent-aging taxonomy, event-driven degradation triggered when a fact changes but the prior value isn't superseded in memory, especially harmful for derived quantities like running totals.
Why it matters: Long-lived AI assistants will keep accumulating outdated facts unless they actively overwrite stale ones, and silent staleness is especially toxic for derived quantities like balances or totals.
For example, an assistant keeps recommending a coworker's old email address weeks after the user mentioned they got a new one, because the new fact didn't supersede the old.
Heard on the show
“The canceled premium plan — that's revision aging.”Episode 086 — Why Frozen-Weight Agents Still Get Worse Over Time