The theme was 'agentic commerce'. I realize this has nothing to do with giving an agent my credit card but I was inspired to build this because there was a lot of discussion about how people were using ChatGPT and the like to recommend stuff to buy.
It's totally free to use, but I got some feedback from the judges that this was genuinely useful, so I added a sign up link at the bottom. If anyone ends up pre-ordering it, I'll build out the functionality to track prompts over time and crawl those webpages to see how often the citations link back to target domains.