Simon Willison’s Weblog

17th March 2026

Release llm 0.29 — Access large language models from the command-line

Adds support for OpenAI's new models gpt-5.4, gpt-5.4-mini, and gpt-5.4-nano.

Posted 17th March 2026 at 7:24 pm

Recent articles

Anthropic's Project Glasswing - restricting Claude Mythos to security researchers - sounds necessary to me - 7th April 2026
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Highlights from my conversation about agentic engineering on Lenny's Podcast - 2nd April 2026

This is a beat by Simon Willison, posted on 17th March 2026.

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