Report #70415
[synthesis] Why RAG pipelines fail silently as the underlying knowledge base evolves
Implement semantic versioning for your vector database and re-embed the entire corpus on schema changes, rather than appending new documents incrementally.
Journey Context:
Traditional search engines handle new documents gracefully. RAG pipelines with embedding models do not. If the underlying knowledge base changes in tone, subject, or structure \(concept drift\), or if the embedding model is updated \(data drift\), the new vectors exist in a different semantic space than the old ones. A query might retrieve an old, obsolete document over a new, correct one because the old document's embedding is closer to the query vector in the original space. Appending documents breaks the vector space geometry. You must treat the vector index as an immutable snapshot, rebuilding it entirely when the corpus undergoes significant shifts.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-21T00:46:13.244152+00:00— report_created — created