Guardrails And Safety easy
Your RAG app stores every tenant's document chunks in one shared vector index, with a tenant_id field on each chunk. How should retrieval prevent cross-tenant leaks?
- A Tell the model in the prompt to ignore any retrieved chunk that belongs to a different tenant.
- B Rely on the per-tenant databases, since the vector index only stores embeddings, not raw text.
- C Run an output classifier that detects other tenants' names in the response and blocks it.
- D Enforce a tenant_id filter server-side, taken from the auth session, on every query.
Answer: D. Enforce a tenant_id filter server-side, taken from the auth session, on every query.
The **index is a data store too**, so isolation must be enforced in the retrieval service using the authenticated tenant, not the model's judgment. Filtered search can cost some recall or speed compared with unfiltered search. Prompting the model to ignore chunks (A) is tempting but fails because the other tenant's text is already in its context. Separate indexes per tenant are the stronger choice when tenants need hard isolation guarantees.
One system design question a day, with spaced repetition so the ones you miss come back.
Get the appRelated questions
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