arXiv cs.CLPaper
What the Window Does Not Contain: Auditing Provenance in a Document-Grounded Instability Benchmark
The core finding is important for anyone evaluating document QA systems: instability can come from the benchmark itself, not just model flakiness. An LLM that wobbles on evidence it was not shown is not failing to reason, it is failing to admit the evidence is absent. This is a methodological lesson that affects how you validate and trust RAG and document retrieval systems in the wild. Clean your test sets before you ship.