Real Agent Cases

Build a terminal-to-HTML sharing tool with Claude Code for web

Source date:
Last verified:
Method:
How we verify

Evidence: Shown on videoThe source includes a video or screen recording of the agent doing the task.

Outcome

Claude Code for web built a terminal-to-html tool that turns pasted terminal output into a shareable gist-preview link, recorded start to finish in an 11-minute video.

Agent

Claude Code for web

Prompt Original prompt

Exact prompt as published in the source.

Build a new tool called terminal-to-html which lets the user copy RTF directly from their terminal and paste it into a paste area, it then produces the HTML version of that in a textarea with a copy button, below is a button that says "Save this to a Gist", and below that is a full preview. It will be very similar to the existing rtf-to-html.html tool but it doesn't show the raw RTF and it has that Save this to a Gist button

That button should do the same trick that openai-audio-output.html does, with the same use of localStorage and the same flow to get users signed in with a token if they are not already

So click the button, it asks the user to sign in if necessary, then it saves that HTML to a Gist in a file called index.html, gets back the Gist ID and shows the user the URL https://gistpreview.github.io/?6d778a8f9c4c2c005a189ff308c3bc47 - but with their gist ID in it

They can see the URL, they can click it (do not use target="_blank") and there is also a "Copy URL" button to copy it to their clipboard

Make the UI mobile friendly but also have it be courier green-text-on-black themed to reflect what it does

If the user pastes and the pasted data is available as HTML but not as RTF skip the RTF step and process the HTML directly

If the user pastes and it's only available as plain text then generate HTML that is just an open <pre> tag and their text and a closing </pre> tag

Source

https://simonwillison.net/2025/Oct/23/claude-code-for-web-video/

By Simon Willison · Published Oct 23, 2025 · Added Oct 15, 2026 · Last verified Oct 15, 2026

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