
GPT-6 Sol, Sonnet 5.5, Astra Shelved: September's Models, Tested
GPT-6 Sol got cheaper without getting smarter, Sonnet 5.5 got much smarter but not cheaper at full effort, and Astra 6.1 never shipped.
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AI is rewriting science, health and work. This section reads the studies and the filings behind the claims, and separates what was demonstrated from what was announced.

GPT-6 Sol got cheaper without getting smarter, Sonnet 5.5 got much smarter but not cheaper at full effort, and Astra 6.1 never shipped.

Four AI agent security stories made September's headlines, and they rest on four very different grades of evidence.

Challenger counts 120,136 announced cuts blamed on AI in 2026. Federal data counts about 1.6 million layoffs every month. Both numbers are true.

A randomized trial of 2,379 students. The tutor was free, patient, and built on GPT-4o. Grades fell anyway.
Hinton, Bengio and about 400 colleagues are asking for an international body to oversee the most capable AI systems. A public call, not yet a policy.
Meta's new flagship scores 56 on an independent index, two points behind Claude Opus 5.5. And the stronger model is not the one you can call today.
No story from a launch post. Every claim traces to a paper, a dataset or a filing, linked at the bottom of the article.
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