Benchmark Almanac

AA-Omniscience

Claude Mythos Preview 70.8% leads since Apr 2026 In use

41-topic closed-book knowledge test. Net score rewards correct answers, penalizes wrong ones and gives zero for abstentions.

Score can be negative (Inkling-Small shows -9).

In the authors’ words

Existing language model evaluations primarily measure general capabilities, yet reliable use of these models across a range of domains demands factual accuracy and recognition of knowledge gaps. We introduce AA-Omniscience, a benchmark designed to measure both factual recall and knowledge calibration across 6,000 questions. Questions are derived from authoritative academic and industry sources, and cover 42 economically relevant topics within six different domains. The evaluation measures a model's Omniscience Index, a bounded metric (-100 to 100) measuring factual recall that jointly penalizes hallucinations and rewards abstention when uncertain, with 0 equating to a model that answers questions correctly as much as it does incorrectly. Among evaluated models, Claude 4.1 Opus attains the highest score (4.8), making it one of only three models to score above zero. These results reveal persistent factuality and calibration weaknesses across frontier models. Performance also varies by domain, with the models from three different research labs leading across the six domains. This performance variability suggests models should be chosen according to the demands of the use case rather than general performance for tasks where knowledge is important.

Abstract of AA-Omniscience: Evaluating Cross-Domain Knowledge Reliability in Large Language Models (arXiv:2511.13029, CC0)
Made by Artificial Analysis Released Nov 2025 Short factual questions Public tasks plus a private test set Last in a launch post Oct 2026 Last model added Oct 2026
Level
Expert Specialists with years of training, often over hours of work
Scored
Checked automatically A program checks the result against an answer key, unit tests or the expected final state.
Answers
Short answer A number, word or short string matched to a key.
17
Models scored in lab cards
15
Launch posts list it, from 7 labs
18
System cards report it, from 5 labs

Claude Mythos Preview leads with 70.8%

Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.

  1. 1 Claude Mythos Preview 70.8%
  2. 2 Claude Opus 5.5 58%
  3. 3 Claude Opus 4.5 51.9%
  4. 4 Muse Spark 1.3 50.8%
  5. 5 Claude Opus 5 49%
  6. 6 Mercury 3 46.4%
  7. 7 Claude Opus 4.8 37%
  8. 8 Claude Sonnet 5.5 35%
  9. 9 Claude Opus 4.7 34.4%
  10. 10 Nemotron 3 Ultra 24.1%
  11. 11 Mercury 2.5 22%
  12. 12 Claude Opus 4.6 20.8%
  13. 13 Claude Sonnet 5 20%
  14. 14 Nemotron 3.5 Lightning 30B-A3B 17.5%
  15. 15 Nemotron 3.5 Bolt 74B-A9B 16.9%
  16. 16 Claude Haiku 5.5 12%
  17. 17 Nemotron 3.5 Super VL 4.03%
#ModelScoreSettingDateSource
1 Claude Mythos Preview 70.8% Apr 2026 Model card
2 Claude Opus 5.5 58% Sep 2026 Model card
3 Claude Opus 4.5 51.9% Nov 2025 Model card
4 Muse Spark 1.3 50.8% Oct 2026 Model card
5 Claude Opus 5 49% Jul 2026 Model card
6 Mercury 3 46.4% Oct 2026 Model card
7 Claude Opus 4.8 37% May 2026 Model card
8 Claude Sonnet 5.5 35% Sep 2026 Model card
9 Claude Opus 4.7 34.4% Apr 2026 Model card
10 Nemotron 3 Ultra 24.1% Jun 2026 Model card
11 Mercury 2.5 22% Sep 2026 Model card
12 Claude Opus 4.6 20.8% Feb 2026 Model card
13 Claude Sonnet 5 20% Jun 2026 Model card
14 Nemotron 3.5 Lightning 30B-A3B 17.5% Aug 2026 Model card
15 Nemotron 3.5 Bolt 74B-A9B 16.9% Oct 2026 Model card
16 Claude Haiku 5.5 12% Oct 2026 Model card
17 Nemotron 3.5 Super VL 4.03% Oct 2026 Model card

2 models have held number one since its release in Nov 2025

Lab claims count from the day the card came out, independent runs from the model’s release.

Anthropic
Lab claims 2 leaders

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

Reported by the lab in its model card Best so far
0% 20% 40% 60% 80% 100% 2026 2027 Near the ceiling (85%) Claude Mythos Preview Claude Opus 4.5 0% 20% 40% 60% 80% 100% 2026 2027 Near the ceiling (85%) Claude Mythos Preview Claude Opus 4.5

6 labs put it in a launch post in the last six months

Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.

Qwen
Liquid AI
NVIDIA
Thinking Machines
Inception Labs
Reflection
Meta
DateLaunch postScoreAs the post writes it
27 Oct 2026 LFM3-1.7B 0.5 AA-Omniscience (public) index 0.50, accuracy 7.07, non-hallucination 92.93
19 Oct 2026 Mercury 3 46.4 AA-Omniscience-Public (Accuracy)
15 Oct 2026 Muse Spark Open 25 AA Omniscience
15 Oct 2026 Nemotron 3.5 Bolt 74B-A9B 16.9 AA-Omniscience accuracy 16.90 (non-hallucination 61.27), not the net index
15 Oct 2026 Nemotron 3.5 Super VL 4.03 AA-Omniscience index 4.03 (accuracy 26.20, hallucination rate 30.0)
13 Oct 2026 LFM2.5-24B-A2B -24.9 AA-Omniscience
5 Oct 2026 Beam 1.0 13 AA Omniscience (index), public split only (our results)
8 Sep 2026 Mercury 2.5 22 Omniscience Accuracy (Non-Hallucination 33)
11 Aug 2026 Nemotron 3.5 Lightning 30B-A3B 17.5 AA-Omniscience (metric not stated)
4 Aug 2026 LFM2.5-2.6B -29.5 AA-Omniscience-Public
30 Jul 2026 Inkling-Small -9 AA Omniscience index
15 Jul 2026 Inkling 2.1 AA Omniscience (Artificial Analysis)
4 Jun 2026 Nemotron 3 Ultra 24.1 OmniScience Accuracy 24.1 (Non-Hallucination 78.7), not the net index
28 May 2026 LFM2.5-8B-A1B -24.7 AA-Omniscience Index -24.70 (Accuracy 8.67, Non-Hallucination Rate 63.47)
20 Apr 2026 Qwen 3.6 Max (Preview) 10 AA-Omniscience Index Knowledge Reliability and Hallucination

18 system cards report it, from 5 labs

Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.

DateDocumentScoreAs the document writes itSection
23 Oct 2026 Muse Spark 1.3 system card 50.8 AA-Omniscience public subset accuracy, Muse Spark 1.3 (API) max (Figure 33b). Non-hallucination rate 69.42 Hallucination
15 Oct 2026 Nemotron 3.5 Super VL technical report AA-Omniscience public 600 questions, Accuracy 26.20 and Non-Hallucination 69.96, no index printed (Table 10) Hallucination
15 Oct 2026 Nemotron 3.5 Lightning 30B-A3B technical report AA-Omniscience Accuracy 17.47 and Non-Hallucination 68.88, BF16, no index printed (Table 22) Hallucination
15 Oct 2026 Nemotron 3.5 Bolt 74B-A9B technical report AA-Omniscience accuracy 16.90 and non-hallucination 61.27, released 24GB checkpoint, no index printed (Table 7). BF16 21.80 and 56.14 Hallucination
13 Oct 2026 Gemini 4 Argon system card 42.4 AA-Omniscience, Omniscience Index 42.4; hallucination rate 15.1% (Figures 5.11, 5.12) Hallucination
7 Oct 2026 Claude Haiku 5.5 system card 12 AA-Omniscience public split, net score 0.12 (correct minus incorrect) (6.3.3.1) Hallucination
28 Sep 2026 Claude Sonnet 5.5 system card 35 AA-Omniscience public split, net score 0.35 (correct minus incorrect), closed book (6.3.2.1, Figure 6.3.2.1.A) Hallucination
22 Sep 2026 Claude Opus 5.5 system card 58 AA-Omniscience public split, net score 0.58 (correct minus incorrect), closed book (6.5.4.1, Figure 6.5.4.1.A) Hallucination
30 Jul 2026 Inkling-Small model card -9 AA Omniscience index (5. Evaluations table) Hallucination
24 Jul 2026 Claude Opus 5 system card 49 AA-Omniscience public split, net score 0.49 (correct minus incorrect), closed book. Correct 0.71, incorrect 0.22, declined 0.07 printed on chart (6.5.1, Figures 6.5.1.A and B) Hallucination
15 Jul 2026 Inkling model card 2.1 AA Omniscience (5. Evaluations table, effort 0.99) Hallucination
30 Jun 2026 Claude Sonnet 5 system card 20 AA-Omniscience, net score 0.20 (correct minus incorrect), closed book. Correct 46.9%, incorrect 26.5%, abstained 26.6% (6.5.1, Figures 6.5.1.A and B) Hallucination
9 Jun 2026 Nemotron 3 Ultra technical report OmniScience Accuracy 24.1 and Non-Hallucination 78.7, no index printed (Table 10) Hallucination
28 May 2026 Claude Opus 4.8 system card 37 AA-Omniscience net score 0.37 (correct minus incorrect), closed book, printed on chart (6.3.3.1, Figure 6.3.3.1.B) Hallucination
16 Apr 2026 Claude Opus 4.7 system card 34.4 AA-Omniscience net score (correct minus incorrect), closed book, printed on chart. Correct 58.2, unsure 17.9, incorrect 23.9 (6.3.3.1, Figures 6.3.3.1.A and B) Hallucination
7 Apr 2026 Claude Mythos Preview system card 70.8 AA-Omniscience correct rate, no tools, value printed on chart; unsure 7.4, incorrect 21.7, net score not printed (4.3.3.1, Figure 4.3.3.1.B) Hallucination
5 Feb 2026 Claude Opus 4.6 system card 20.8 AA-Omniscience net score (correct minus incorrect), extended thinking, value printed on chart; correct rate 49.3, net 16.2 with thinking plus effort, net 11.5 without thinking (Figure 4.2.C) Hallucination
24 Nov 2025 Claude Opus 4.5 system card 51.9 AA-Omniscience correct rate, 16k extended thinking, graded by Claude Sonnet 4.5 (Figure 4.1.C; incorrect 36.6%, uncertain 11.5%) Hallucination

Versions

More in Factuality

All 70 in Factuality
  • SimpleVQA In use Models answer 2,025 short factual questions about images across 9 tasks and 9 topics. An LLM judge grades answers against fixed references. Qwen3.7-Plus 81.7%
  • HallusionBench In use Models answer 1,129 yes or no questions about 346 images, built in pairs to expose language hallucination and visual illusion. Scored by accuracy. Keye-VL-2.0-30B-A3B 73.5%
  • SimpleQA Verified In use 1,000 human-verified, de-duplicated short-answer factual questions measuring parametric knowledge. Gemini 3.1 Pro 77.5%
  • GaRAGe In use Models write long-form RAG answers to 2,366 questions with human-annotated grounding passages. Scoring checks whether answers use the relevant passages. Nemotron 3.5 Bolt E4B 40.7%
  • Kimi Hallu Bench In use Models answer hard prompts drawn from practical work tasks. Fact-checking agents score the share of claims that are hallucinated. Kimi K3.1 Pro 8.30%
  • RAGTruth In use A word-level annotated corpus of hallucinations in retrieval-augmented generation answers. It is used to train and evaluate hallucination detection and RAG faithfulness. Nemotron 3.5 Bolt E4B 77.9%