← Concept IndexDEFINITION WHY IT MATTERS COMMONLY CONFUSED WITH
Keeping knowledge fresh
Also called: stale index, re-indexing, out-of-date sources
A retrieval system is only as current as its index. Keeping answers fresh means updating that index as sources change, and knowing how stale the underlying documents might be.
RAG sidesteps the model's training cutoff, but it introduces its own: if the index isn't refreshed, the system cites outdated policies or prices with total confidence. 'Source-backed' doesn't mean 'up to date' unless someone keeps the sources current.
The model's knowledge cutoff. That's a fixed property of training; index staleness is an operational choice you control by re-indexing — and forget to at your peril.