While OpenAI’s GPT-6 Astra is making a big splash in the AI world with its debut, it was far from the only one to be announced this week. When there’s a new, updated model seemingly every other day, it’s hard to stay up to date, let alone be excited, but the onslaught of new offerings is something to note. It wasn’t just OpenAI: Fellow AI heavy hitters Anthropic, Meta, and Google also announced updates to AI models. While each new model has its own strengths, a focus we’re seeing more and more often is advancements in agentic AI workflows, and each new announcement spotlight on those capabilities.
Below, we’ll break down all of the latest models from this week and give you the details.
GPT-6 Astra #
Of all models released this week, OpenAI’s is the only one that’s not a “.x” update. GPT-6 Astra is said to excel in cybersecurity and software engineering, and OpenAI calls it its most intelligent model yet. The performance benchmarks for Astra have it ahead of its competitors in a lot of ways, making it one of the most advanced models we’ve seen to date.
OpenAI is also touting Astra’s strength in multi-step agentic workflows, scientific discovery and financial modeling. The model is also said to be much better at computer use, which was a focus of its predecessor, ChatGPT 5.6, when it was released in July.
ChatGPT-6 Astra is rolling out to people with Daybreak access, its program for “vetted enterprise customers and cybersecurity practitioners.” OpenAI says that the new model will roll out to Plus, Pro and Business users over the coming days.
(Disclosure: Ziff Davis, CNET’s parent company, in 2025 filed a lawsuit against OpenAI, alleging it infringed Ziff Davis copyrights in training and operating its AI systems.)
Claude Fable 5.1 and Mythos 5.1 #
Anthropic announced updates for its Fable and Mythos models — both of which are some of the best available today. Anthropic says that both Fable 5.1 and Mythos 5.1 are the same model, but each has a different set of safeguards. Fable is the model that the average person can use, and Mythos is typically reserved for researchers and cybersecurity experts.
Anthropic says its latest models have significantly better performance over their predecessors, and the release “sets a new standard” for coding, knowledge work and long-running problem-solving tasks. It also says that Fable 5.1, when set to low or medium effort, has performance similar to Fable 5 but at a much lower cost.
Fable 5.1 is available to the general public, whereas Mythos is limited to Anthropic’s trusted access programs.
Muse Spark 1.3 #
Meta released a model this week that should bring it back up into the conversation about the most capable models around. Muse Spark 1.3 brings more advanced reasoning and better performance in agentic and coding tasks.
Meta said this model is trained to collaborate with the person using it, and will ask clarifying questions when a prompt is vague and check to confirm the actions it will perform in agentic workflows.
Must Spark 1.3 is available in Muse Code and Meta’s Model API.
Gemini 3.8 and 3.8 Flash Cyber #
Google released two new models in the form of Gemini 3.8 Flash and 3.8 Flash Cyber. This was hot on the heels of the release of Gemini 3.7 Flash on Aug. 13. The latest additions to the family are said to offer “next-generation intelligence” for agentic workflows and cybersecurity.
Gemini 3.8 Flash is available to enterprise, consumer and developers across Google products, where 3.8 Flash Cyber is currently available in limited access to participants of the Fairwind Program, which was also announced the same day as the new models.