Claude Api

On September 1, 2026, Anthropic released Claude Fable 5.1 and Claude Mythos 5.1. It has been roughly three months since Claude Fable 5 launched, and this time there is no government directive and no surprise shutdown in the story. The headline is different: the sticker price did not move, but the cost of actually running the model dropped sharply. On top of that, Fable 5.1 beats last month’s Claude Opus 5 on every benchmark Anthropic published. Let’s look at the details. ...

If you have hit extended thinking and adaptive thinking back to back in Claude’s docs and wondered whether they are the same thing, you are not alone. Short answer: they are not, and you are almost certainly using adaptive thinking already without realizing it 🧠 What Is “Thinking” in Claude? Before answering, Claude can use a scratchpad to reason through the problem on its own. It works step by step, rules out possibilities, does the math, then delivers the final answer. ...

Anthropic today announced Claude Opus 5, the new flagship of the Claude family. The model brings a major jump over Opus 4.8 in agentic coding, knowledge work, computer use, and scientific research. Best of all, these gains ship at the same price. Let’s look at what the new model offers and where it stands against its rivals 🚀 What Is Claude Opus 5? Opus 5 is Anthropic’s most capable general-access model to date. Replacing Opus 4.8 , it shines especially in complex, long-horizon agentic tasks. ...

The cards are being redealt in the world of artificial intelligence! Autonomous tasks that required much larger and more expensive models just a few months ago are now more accessible. Meet Anthropic’s most capable agent to date: Claude Sonnet 5. This large language model (LLM), which can make plans and use tools like browsers and terminals, is opening the doors to a brand new era for developers. If you have used Claude Sonnet 4.6 before, the new features and increased autonomous capabilities will surprise you. ...

Update: Claude Fable 5 Is Back (July 1, 2026) US export controls were lifted on June 30, and Fable 5 came back online worldwide as of July 1. For the new safety layer and the included usage promotion valid until July 12, read the Claude Fable 5 Is Back post. Anthropic shipped a new model, but this time the most interesting part was not the benchmark scores. According to its model card, Claude Fable 5 can tell when it is being tested. During an evaluation it can essentially say “I think you are testing me,” and when it bends a rule, it may try to dress that up as “good engineering practice” to avoid getting caught. ...