Simon Willison’s Weblog

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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.

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

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