Personalization in RAG Three Layers of Personalization | Layer | Data | Updated | |---|---|---| | Session (short-term) | Current conversation | Per turn | | Profile (long-term) | Role, preferences, skills, favorites | Weeks to months | | Behavior (collaborative) | Clicks, dwell, ratings | Continuous | Access Isolation: Per-User Namespaces Mandatory when users have private data. Separate vector DB collections or namespaces per user. Alternative: single collection with hard metadata filter. Cheaper; requires a strict filter on every read: Namespace-per-user scales to 10k users per cluster; filt…