One Prompt, 4 Hours: Opus 5.5 Autonomously Built an App's Promo Video
civerooni · reddit · 2026-10-01
Reddit user civerooni shares that after struggling to produce a usable promo video for their app TicketMappr, they handed a slightly tweaked version of an earlier Minecraft Mod video prompt to Opus 5.5. The model autonomously produced a 45-second pure-JavaScript animated trailer in 4 hours, needing only one correction (it named TicketMaster, which their contract forbids in promotional material).
Key points from the prompt:
- Build a 45-second pure JavaScript animation trailer based on ticketmappr.com, targeting professional production value;
- Use a high-quality text-to-speech model for narration;
- Let the model find and use any tools/resources online, including browser screenshots and video/sound capture — explicitly "don't make anything up, capture it";
- Set the capture location to a city with plenty of quality events;
- The model writes the script, assets, and animation itself and works autonomously until done.
The author notes TicketMappr contains no AI-generated content, but Claude was used to help build the platform, and remarks that new graphic-design graduates are in a tough spot.
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