Command Query Responsibility Segregation. Separate models for writing data and for reading it, often with a read store shaped for the queries.
You have done this if
You wrote documents to a source system and served search from a separate index built for reading.
Say it in a review
Writes go to the system of record; reads come from an index built for retrieval, which is CQRS in practice.
On the AI Application map Sources, Vector Index