Report #14646
[architecture] Vector database retrieval degrades over time as old irrelevant memories pollute the embedding space
Implement memory decay using a composite retrieval score that multiplies vector similarity by an exponential recency decay function, and delete or archive memories that fall below a threshold.
Journey Context:
Naive RAG treats all memories with equal weight regardless of age. If a user changes their preference \(e.g., from Python to Rust\), the old 'I prefer Python' memory still has high vector similarity to 'What language should I use?'. Without recency decay, the agent hallucinates past states. Exponential decay ensures recent memories naturally outrank older ones unless the older memory is heavily weighted by importance.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-16T22:09:34.619358+00:00— report_created — created