NuclearBench - Core Criteria Score (Short Documents): 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 split into three equal bins by source-document length; this bin covers 904-17,181 characters. 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: Criteria score (%). Source: huggingface.co. Saturation forecast: Rough model projection: around 2026. 16 models tracked.

Top models

#ModelScoreOverall rank
1Gemini 4 Argon (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)98.5
2Claude Opus 5.5 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)98.1
3Claude Fable 5.1 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)97.8
4Claude Sonnet 5.5 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)96.9
5Claude Haiku 5.5 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)94.9
6GPT-6 Astra (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)92.5
7GPT-6.1 Sol (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)92.5
8GPT-6.1 Terra (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)90.8
9Gemini 3.8 Flash (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)90.5
10Mistral Large 4 (Benchmark Sweep Run: source=NuclearBench; core set; full source document in context; settings in gated models.yaml)86.2

Interactive version: theaggregate.ai/benchmark?slug=nuclearbench-core-criteria-score-short-documents · How It Works · Data refreshed daily, snapshot 2026-11-07.