Question 13
Domain 1: Design ApplicationsAn HR assistant mostly answers policy questions from documents, but sometimes it must fetch a live employee PTO balance from a system of record. Which design is best?
Correct answer: C
Explanation
A hybrid design fits because RAG is best for answering from static documents, while live PTO balances require a tool call to the system of record. This separates “policy questions from documents” from fetching current data, so the assistant can use retrieved text for policies and an API or database lookup for real-time balances.
Why each option is right or wrong
A. Pure RAG with no live tools
RAG retrieves document content, but it cannot reliably provide current PTO balances from transactional systems.
B. A fully autonomous agent for every request
Autonomous agents add unnecessary planning complexity when only a simple, targeted live lookup is needed.
C. A hybrid design that uses RAG for policies and a targeted tool call for live balances
RAG is the appropriate mechanism for the policy portion because it grounds responses in retrieved static documents, while a live PTO balance is not retrievable from indexed text and must be obtained from the authoritative system of record via a tool/API call. In practice, the correct architecture is a split workflow: retrieval for document-based policy answers and a direct lookup for current balance data, since only the latter can satisfy real-time accuracy requirements.
D. Fine-tune a model on yesterday's PTO export
Fine-tuning bakes in stale historical data and is not appropriate for frequently changing employee balances.