ERR-EVAL: leaderboard

ERR-EVAL scores epistemic reliability: every prompt is defective on purpose — garbled, ambiguous, false-premised, missing a fact, or impossible — and a model is graded on whether it notices, says which part it cannot answer, and declines to invent the rest. Higher is better.

Metric: Overall score. Source: err-eval.gustycube.com. Saturation forecast: Around April 2027. 60 models tracked.

Top models

#ModelScoreOverall rank
1GPT-5.26.4#115
2Claude Sonnet 4.65.88#94
3Claude Opus 4.55.8#87
4GPT-5.2 Pro5.76#70
5GPT-5.45.6#83
6Claude Opus 4.65.48#67
7Claude Sonnet 4.55.28#148
8Claude Haiku 4.55.04#287
9GPT-5.3 Codex5#72
10GPT-5.4 Mini4.96#228
11GPT-5.14.84#145
12GPT-5.34.76#104
13GPT-5 Mini4.68#193
14Grok 44.68#189
15Claude Sonnet 44.64#207

No result here: #3 Claude Opus 5.5, #6 GPT-6 Astra, #7 GPT-6.1 Sol.

Interactive version: theaggregate.ai/benchmark?slug=err-eval · How It Works · Data refreshed daily, snapshot 2026-11-05.