Do I need RAG?

• Ask whether the answer depends on external knowledge and whether the corpus is too large or variable to supply directly.
• Use RAG for private/changing knowledge with source references; use exact tools for live records.
• If a handful of permitted documents are already known, compare direct long-context processing.

Failure policy: no applicable evidence → abstain or search-only/staff path; search unavailable → report service failure, not a confident policy answer.