Generate a colophon page for a GitHub Pages site with Claude Code
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- by Simon Willison
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Evidence: Screenshots or logsThe source shows screenshots, a transcript or the agent's output.
Outcome
Claude Code wrote a script that builds a mobile-friendly colophon page listing every tool and its commit history, then wired it into the GitHub Pages deploy workflow.
Agent
Prompt Original prompt
Exact prompt as published in the source.
Write me a new script called build_colophon.py which looks through that gathered JSON file and builds and saves an HTML page. The page should be mobile friendly and should list every page—with a link to that page—and for each one display the commit messages neatly (convert newlines to br and linkify URLs but no other formatting)—plus the commit message dates and links to the commits themselves which are in https://github.com/simonw/tools
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Optional stronger version
Our rewrite with extra checks. The poster didn't test it.
Goal: Write build_colophon.py that turns the gathered commit JSON into a mobile-friendly HTML colophon page. Inputs (fill in or confirm): - Path to the gathered JSON file and its structure (page → commits) - Output path for the HTML page - Site base URL for page links Rules: - List every page with a link to it; under each, show its commit messages in date order. - Convert newlines to <br> and linkify URLs, with no other formatting; escape all other HTML. - Use plain HTML and inline CSS only; readable at 375px wide. - Keep the script dependency-free (standard library only). - Make the page readable on a phone with no horizontal scrolling. Checkpoint: Don't commit or push; leave the script and output for my review. If you get stuck: If the JSON shape differs from what you expect, print a sample and stop instead of guessing. If a login, CAPTCHA or two-step code appears, stop and ask me to handle it; never guess or store passwords. Verify before you finish: Run it, open the output, and check one page with a multi-line message and one with a URL render correctly. Output: The script, the generated HTML and a short note on how to rerun it. Done when: the page lists every page with correctly escaped, linkified commit messages.
Source
https://simonwillison.net/2025/Mar/11/using-llms-for-code/
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