NuclearBench - Core FineSurE Faithfulness: leaderboard
Long-document nuclear regulatory and engineering question answering: models receive the full source document and are graded for rubric criteria coverage and sentence-level faithfulness. NuclearBench (Atomic Canyon with Idaho National Laboratory SMEs): 280 published questions over 247 public NRC and nuclear technical documents; the model receives the question and the complete source document (no retrieval). CriteriaJudge marks each rubric criterion met or not met without the document; criteria score is the mean per-question fraction met. FineSurE classifies each answer sentence against the document; the score is the mean share of error-free sentences. The 125-question holdout is not used. Per-model temperature, reasoning effort and provider pins are kept in the gated models.yaml; the public card names no judge model. Core set (219 questions). Question access: The question and document files on Hugging Face require accepting access terms (unauthenticated README is public; models.yaml and JSONL return 401). A 125-question holdout is withheld.
Metric: FineSurE faithfulness score (%). Source: huggingface.co. Saturation forecast: Rough model projection: around 2026. 16 models tracked.
Top models
| # | Model | Score | Overall rank |
|---|---|---|---|
| 1 | GPT-6.1 Terra (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 94.9 | |
| 2 | GPT-6.1 Sol (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 93.7 | |
| 3 | GPT-6 Luna (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 93.4 | |
| 4 | DeepSeek V4 Pro (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 93.3 | |
| 5 | GPT-6 Astra (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 92.7 | |
| 6 | Claude Opus 5.5 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 91.5 | |
| 7 | Claude Fable 5.1 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 91.3 | |
| 8 | Nemotron 3.5 Super VL (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 90.5 | |
| 9 | Gemini 3.5 Flash-Lite (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 90.4 | |
| 10 | Gemma 4 31B (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml) | 90 |
Interactive version: theaggregate.ai/benchmark?slug=nuclearbench-core-finesure-faithfulness · How It Works · Data refreshed daily, snapshot 2026-11-07.