The name is the button.

An agent writes the code now, and a human thumb hovers over Accept all a hundred times a day. The honest question of this decade is what, exactly, you just accepted. So I read the diff.

Eight years as a backend engineer in Stockholm, back in Tokyo since 2023, and I still ship something small most nights, usually badly. My one rule: the only real review of a model is the thing you built with it. That is why there is no leaderboard on this site.

Around a hundred and forty sources come through — the labs' own posts, the papers, the tools, the runtimes and languages nobody is watching yet, the chip under the demo, and the newsletters people actually forward. What is moving gets counted so the week reads at a glance, and every few days I explain one mechanism in plain words.

A story here is a headline, a short excerpt, one image and the link to whoever wrote it. We never reproduce the post; the images belong to their authors. A post written in Japanese appears in Japanese, exactly as it was published, and the link goes to the original.

— Yuki Halvorsen, Tokyo

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Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price war

September 22

Yesterday was Grok 4.7 ( pelicans ) and MiMo v2.6 Flash/Pro ( more pelicans ). Today Anthropic released Claude Opus 5.5 , and around an hour later OpenAI released GPT-6 Sol and GPT-6 Luna .

Models & releases ai openai generative-ai llms

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Claude Opus 5.5, GPT-6 Sol, GPT-6 Luna, and a new price war

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JapanAnthropic、「Claude Opus 5.5」公開 Fable 5.1並みの性能で利用コスト4割減 ITmedia AI+

ValleySnorkel AI triples valuation to $3.5B as demand for AI training data booms TechCrunch AI

ValleyNew Anthropic, OpenAI models make same promise: A little more for a lot less money Ars Technica AI

GitHubClaude Opus 5.5 wants to finish your coding tasks, not just start them The New Stack

GitHubGPT-6 Sol closes most of the alignment gap with Astra. It’s one-fifth the price. The New Stack

LabsBring more intelligence to everyday work with GPT-6 Sol and GPT-6 Luna on Amazon Bedrock AWS Machine Learning