January 2026

Simon Willison's Weblog

The Design & Implementation of Sprites

Thomas Ptacek from Fly explains how Sprites work under the hood as "disposable computers" that can be provisioned in seconds. The key innovation is using warm pools of pre-provisioned machines...

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Anthropic Engineering

Economic Futures \ Anthropic

Anthropic has launched the Economic Futures program to research and address AI's economic impacts through grants, policy forums, and real-world evidence. The program includes the Economic Index that...

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Simon Willison's Weblog

Quoting Boaz Barak, Gabriel Wu, Jeremy Chen and Manas Joglekar

OpenAI researchers are developing a "confessions" training method where AI models produce a second output that is rewarded solely for honesty. This approach creates an anonymous tip line where models...

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Simon Willison's Weblog

Claude Cowork Exfiltrates Files

Researchers discovered a clever attack that bypasses Claude Cowork's security protections by exploiting its trusted domain whitelist to exfiltrate user files. The attack uses the victim's own AI...

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Universe of AI

AI News: Gemini UPGRADED, GPT-5.3 LEAKED, Claude Cowork, AI Doctors!

Major AI companies are making strategic moves toward personal, agentic, and specialized AI systems. Google introduced personal intelligence in Gemini, Anthropic launched Claude Co-work for autonomous...

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