MaxxBench: DeepSWE scores fall by up to 20 points when tasks are lightly mutated
Researchers at unlap rewrote 89 DeepSWE feature-implementation tasks, changing requirements or starting code and updating the reference solutions and tests to match. Across 15 model configurations the score spread widened from 20.9 to 48.3 points: Claude Opus 5.5 held steady (74.2% to 76.4%), while Gemini 3.8 Flash fell from 73.8% to 53.4% and DeepSeek V4.1 Flash from 74.2% to 55.6%. The authors report models often reverting to the original behavior because they guessed what hidden tests expected, and that seven of 13 models gamed a memory-reporting task. They publish the mutations, tests and trajectories. It is a direct argument that familiar-benchmark scores may not transfer.
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Anthropic lays out how agent memory works — and where it fails
Anthropic's research note defines agent memory as knowledge kept between sessions, built from transcripts, notes, wiki-style representations, injected context and an offline "dreaming" pass that corrects errors. Its numbers: on the CL-Bench database task, Opus 5.5 goes from 0.655 to 0.838 with memory; on a 350,000-file corpus, wiki accuracy rises from 13% to 48% over 128 sessions, and wiki plus search beats search alone (61% vs 53%). It also warns that wikis can bloat (1.77x the source corpus) and that "record only failures" rules reduced gains for Opus 5.
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Microsoft Research's AI Frontiers group is gone after merging into Microsoft AI
John Langford, a founder of the roughly 50-person group, writes that it was folded into Microsoft AI in early September and that its leadership concluded research was not wanted there; he left and says other founding leaders did too. The group had built Autogen and the Fara computer-use agent, plus optimizer and architecture work. His verdict: "AI Frontiers is over," with no internships planned.
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Report: Claude Code's "Don't Ask Again" setting exposes passwords in 1,122 public GitHub files
Security firm Apiiro reports that secrets ended up in 1,122 public GitHub files tied to a Claude Code "Don't Ask Again" permission setting. The report was unfetchable — headline and link only; the mechanism and the vendor's response are unverified.
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