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Exhibit No. 019 · Animation

Analog clock at 10:10

From the AI World Clocks site that topped Hacker News: draw an analog clock showing a given time, with a moving second hand.

Prompt

> Create HTML/CSS of an analog clock showing 10:10AM. Include numbers (or numerals) if you wish, and have a CSS animated second hand. Make it responsive and use a white background. Return ONLY the HTML/CSS code with no markdown formatting.

What it tests

Simple-looking spatial reasoning: numerals in the right places and hands pointing at the right time.

Origin

Brian Moore, AI World Clocks · 2025

Difficulty

●●●

Results

Claude Opus 5.5

Run on 2026-10-19Open the raw answer

Both hands point at 10:10 and the second hand sweeps. The original site fills in the current time every minute and caps answers at 2,000 tokens; here the time is fixed and there was no token cap.

Test conditions

One attempt per test, with no edits after running. Where a first attempt didn’t work, the test was answered once more and the exhibit says so; answers that still don’t work are not shown. Run inside a Claude Code agent session, which includes its own system prompt, rather than the raw API.

All results for Claude Opus 5.5

Save the answer as a .html file and open it in a browser to compare it with the one above.

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