Simon Willison’s Weblog

19th November 2025

Tool XML Well-Formedness Validator — Check XML documents for well-formedness by pasting content into the input area and clicking the validate button. The tool parses the XML and displays any syntax errors with precise line and column information, highlighting the problematic line in the code view below.

Posted 19th November 2025 at 8:06 pm

Recent articles

Some thoughts on the Navier–Stokes Millennium Prize Problem - 8th September 2026
The Pelican comparison grid for Astra is pretty interesting - 4th September 2026
OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026

This is a beat by Simon Willison, posted on 19th November 2025.

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