Users will find Opus 4.8 to be a modest but tangible improvement on its predecessor. There’s still more to be done: we’re working on developing and releasing models that provide many of the same capabilities as Opus at a lower cost. Not only that, but we plan to release a new class of model with even higher intelligence than Opus. As part of Project Glasswing, a small number of organizations are currently using Claude Mythos Preview for cybersecurity work. Models of this capability level require stronger cyber safeguards before they can be generally released. We’re making swift progress on dev
Introducing Claude Opus 4.8… There’s still more to be done: we’re working on developing and releasing models that provide many of the same capabilities as Opus at a lower cost. Not only that, but we plan to release a new class of model with even higher intelligence than Opus. …
… A step forward on safety As we state in our system card , Claude Opus 4.5 is the most robustly aligned model we have released to date and, we suspect, the best-aligned frontier model by any developer. …
… We stated that we would keep Claude Mythos Preview’s release limited and test new cyber safeguards on less capable models first. …
… Most AI policy conversation today centers on the model, and understandably so. The model is where core capabilities come from, and as our most recent release showed, a single generation can meaningfully shift what agents are able to do. …
… We also release an interactive frontend for exploring NLAs on several open models through a collaboration with Neuronpedia . We have also released our code for other researchers to build on. …
… It plans more carefully, sustains agentic tasks for longer, can operate more reliably in larger codebases, and has better code review and debugging skills to catch its own mistakes. And, in a first for our Opus-class models, Opus 4.6 features a 1M token context window in beta 1 . …
… We will share our findings on emerging model capabilities and risks, participate in joint safety and security evaluations, and collaborate on research with Australian academic institutions. …
… On the other hand, the better the models get, the more space there is to develop harnesses that can achieve complex tasks beyond what the model can do at baseline. …
… For those on our Free and Pro plans , Claude Sonnet 4.6 is now the default model in claude.ai and Claude Cowork . …
… This includes creating public goods—like model benchmarks, datasets, and knowledge graphs—to ensure AI tools for math tutoring, college advising, and curriculum design are effective. The first of these will be released publicly later this year. …