The 60-second answer
Build RAG as ingestion/chunking, embedding/indexing, retrieval, optional reranking, prompt construction, and generation. Evaluate retrieval recall separately from grounded answer quality.
Build the answer in this order
1
Define the mechanism
Build RAG as ingestion/chunking, embedding/indexing, retrieval, optional reranking, prompt construction, and generation.
2
Explain the architecture
Evaluate retrieval recall separately from grounded answer quality.
3
Compare trade-offs
Preserve citations and metadata so generated claims can be traced to evidence.
4
Close with serving + evaluation
Add abstention/fallback behavior when retrieval confidence or coverage is weak.
A useful interview mental model
This is the shape of a strong answer—not a script to memorize.
01Definition
02Mechanism
03Trade-offs
04Failure modes
05When to use
Senior-level signal
- Handle ACLs, freshness, deletion, and index versioning as first-class requirements.
- Diagnose retrieval failure separately from generation failure before tuning the LLM.
What the interviewer is really testing
Understanding beyond prompting: architecture, retrieval, evaluation, inference, safety, latency, cost, and failure recovery.
Likely follow-up questions
What assumption makes this approach work?
When would you choose the strongest alternative instead?
What production or data failure mode changes your answer?
Common weak-answer patterns
- Reciting a definition without mechanism or assumptions.
- Claiming one technique is always better without a data regime.
- Stopping before failure modes, validation, or deployment implications.