Simon Willison’s Weblog

The Resource Expert Droid. Like the HTML Validator but for your server’s HTTP headers—extremely useful.

Posted 25th June 2009 at 10:06 am

Recent articles

Large Language Models can run tools in your terminal with LLM 0.26 - 27th May 2025
Highlights from the Claude 4 system prompt - 25th May 2025
Live blog: Claude 4 launch at Code with Claude - 22nd May 2025

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