Definition
Plain language
When repeated summarizing of an AI assistant's memory slowly erases the specific facts.
As stated in the literature
In the agent-aging taxonomy, accumulation-driven degradation where lossy compaction across sessions progressively blurs specific values (numbers, names, dates) into generalities while preserving fluent prose.
Why it matters: It explains why long-lived AI assistants seem to grow vaguer over time, and points to which kinds of facts (numbers, names, dates) need protection from lossy compression.
For example, after many summarization passes, an assistant remembers 'the user travels frequently for work' but has lost the original 'flight UA417 on March 3 to Denver.'
Heard on the show
“The metoprolol dose becoming "a daily medication" — that's compression aging.”Episode 086 — Why Frozen-Weight Agents Still Get Worse Over Time