…Nevertheless, these findings challenge some common intuitions about what language models are capable of—and since we found that the most capable models we tested (Claude Opus 4 and 4.1) performed…
…some new models clearly improve over their predecessors, but others don’t. On locomotion tasks, frontier models can now perform limited but meaningful whole-body control. Newer models make progress on low…
…for example, the UK’s AI Security Institute (AISI) made it a major part of how they evaluate models for their propensity to sabotage AI research. We’re now updating Petri to…
…Indeed, this model performs better on (an older version of) our automated alignment assessment. This is consistent with the fact that Claude Sonnet 4.5 reached a blackmail rate near zero by…
…Importantly, these sorts of attacks also degrade model capabilities—sometimes substantially. On GPQA Diamond , a benchmark which measures PhD-level concepts in biology, chemistry, and physics, model performance dropped from 74% to…
…Fable 5 users will now experience many fewer “fallbacks”—where the system switches to a less capable model after they make a biology-related query. In our testing, this update reduced biology…
…It tied for the top overall score across our six modules at 0.715 and delivered the most consistent long-context performance of any model we tested. On General Finance—our largest…
…The model’s capabilities are also reflected in the experiences of early customers: We're seeing state-of-the-art coding performance from Claude Sonnet 4.5 , with significant improvements on longer…
…time-of-release, the performance of models prior to Opus 4.5 follows a log-linear trajectory, with a mean doubling time of 1.1 months. Our models since Opus 4.5…
…Timeline and safeguard updates We released Fable 5 and Mythos 5 on Tuesday, June 9. They both share the same underlying model, but Fable 5 was released with strong safeguards to make…