Introducing the world’s most powerful model, at least by some measures like Artificial Analysis or any standard benchmark list, which is now Claude Opus 5.5.
Claude Opus 5: The System Card
Claude Opus 5 is trying to be the best of both worlds.
Announcing VibeBench: The AI benchmark that measures what matters — how models like Opus-4.7 actually feel to use in real-world work.
My coworkers and I have been long-time users of Claude Code and Codex and are getting a ton of exposure to other models due to our deep dives into…
Claude Fable 5.1 and Mythos 5.1: The System Card
At the time of its release Claude Fable 5.1 was, by a healthy margin, the most capable publicly available AI model in the world.
Claude Opus 4.8: Capabilities and Reactions
You need a lot of data points to understand a new model, and what you have.
Introducing Claude Opus 5.5
Claude Opus 5.5 leads in agentic coding and knowledge work, and costs 40% less to run than Opus 5 on typical workloads.
The AI Model That Was Too Dangerous to Release: Meet Claude Mythos
Anthropic just built the most powerful AI in history. Then decided the world wasn’t ready for it. Here’s everything you need to know.
Claude Fable 5 and Mythos 5: The System Card
First things first: Claude Fable 5 is the new best publicly available model.
Opus 4.7 Part 2: Capabilities and Reactions
Claude Opus 4.7 raises a lot of key model welfare related concerns.
Claude Opus 5 Is Highly Capable, But Is No Mythos
Claude Opus 5 is a weirder than usual release to evaluate, for two reasons.
Opus 4.7 isn't dumb, it's just lazy — Shimin Zhang
Some follow up experiments with Claude Opus 4.7 based on Simon Willison's Pelican Benchmark Shocker.
Introducing Claude Opus 5
Opus 5 is a step change improvement for the Opus tier powering long-running agents while delivering improvements in coding and professional work.
Introducing Claude Fable 5.1 and Claude Mythos 5.1
Our most advanced models for coding and knowledge work. Their research capabilities also offer an early glimpse of how AI models will contribute to scientific progress.
Opus 5 is a great model. It's not great enough.
Looks not too impressive in this graphics. This is ~ on par with Opus 4.7, apparently. Opus 4.7 was >20x the cost. Full comparison: artificialanalysis.ai/models/comparisons/mimo-v2-5-… (Stated facts *not* independently verified by me! I'm not even sure I am reading that page right)
mr. TIM
Korean lab, Motif, releases a 341B model that performs on par with DSv4 (1.6T) they have some actual architectural innovations and a detailed tech report huggingface.co/Motif-Technologies/Motif-3-Be…
