Some users may not see some documents. Where must this be enforced?
Why B is the answer
At retrieval, by each user's permissions
Filter before the content reaches the model.
In detail
- Filter before the content reaches the model.
- Filter before content reaches the model.
Use case
An illustrative scenario, not a real incident.
A contractor must not see HR files, so retrieval filters by that user's permissions.
See it in different ways
flowchart LR A["Input checks"] --> B["Least-privilege tools"] B --> C["Output checks"] C --> D["Audit log"]
stateDiagram-v2 [*] --> Parse: layout-aware Parse --> Index Index --> HybridSearch: keyword and vector HybridSearch --> Permissions: filter by user Permissions --> Rerank Rerank --> [*]
sequenceDiagram participant P0 as User participant P1 as Retriever participant P2 as Model P0->>P1: Question and identity P1->>P2: Only permitted passages P2-->>P0: Answer
Key point: Enforce permissions at retrieval.
Why the other options are wrong
- A. In the tokenizer's vocabulary file
- A vocabulary file holds no permissions.
- C. In a line of the system prompt only
- A prompt is not a boundary.
- D. After the answer is shown to the user
- That is too late.