Skip to Main Content

Called it

Built at The Persistent Context Sprint Hackathon | Live at MongoDB .Local Build Fest · Aug 13, 2026 · San Francisco, CA

Called it — Demo video

Short description: A prediction game where confidence is billed. Stake tokens on everyday calls; Atlas Vector Search finds the same wrong take you made before and Claude roasts you for it. Long description: Called It — everyone claims they called it; nobody keeps the receipts. Players stake simulated tokens on everyday predictions with a confidence score. Confidence sets the price: a 95% call costs 860 and returns 905, a 30% call costs 340 and returns 1,133. Overconfidence is punished by arithmetic, not by a rule. ▎ ▎ Every prediction is embedded with Voyage voyage-3 and stored in MongoDB Atlas. Pull the receipts runs Atlas Vector Search over one player's own history and hands the nearest past calls to Claude, which roasts them citing specific dates and confidences — surfacing that one player made the same wrong call four times in different words. Before a new call is billed, the same retrieval powers a risk desk that quotes the player's real accuracy on that topic back at them. p.s. in the long term we plan on implementing friends voices to troll your other friends when playing using eleven labs.

Team