H
Gallery/第3回 AI Agent Hackathon with Google Cloud/魔法の天秤 with Gemini
魔
Excellence Award — 第3回 AI Agent Hackathon with Google Cloud 2025

魔法の天秤 with Gemini

A physical device that turns a petty argument into a debate tournament. Each side speaks in turn; the speech is transcribed and an LLM moderates, scoring on logic and whether claims are backed up. The score travels over MCP to BLE motor control and appears as the tilt of real scales. Swap the prompt and the rules change.

Event
第3回 AI Agent Hackathon with Google Cloud
Organizer
Zenn (Classmethod) / Google Cloud Japan
Year
2025
Region
Japan
Prize
Excellence Award
Tech
GeminiModel Context Protocol (MCP)BLEM5StackM5 DialSTT

From the organizer's citation (summary)

Judges praised the idea of taking something people find awkward to ask another person — but easy to ask an AI — and turning it into play. They talked about how many ways of playing could grow out of it, and voiced hope that it spreads widely.
A summary of the commentary the organizer published. See the source for the original wording. Zenn (Classmethod) official results

Why It Won — our reading

Where the judges highlighted the idea, our reading is that the choice of output medium did much of the work. The verdict is not a number on a screen; it is the tilt of a balance, so everyone in the room receives the result at the same moment, bodily. Putting MCP at the seam between the language model and the hardware is a design decision worth explaining on stage, too. And because the rules live in the prompt rather than the firmware, there is room left for new ways to play.

This is our own analysis based on the official announcement and the project's own materials. It is not the organizer's stated reasoning.
AD — Advertisement

More winners from this event

2025フ
Grand Prize

フクシア

第3回 AI Agent Hackathon with Google Cloud
An agent aimed at the paperwork load on social workers. It fills a client's assessment items from an interview transcript, then searches a custom RAG index of support programmes in Yamagata Prefecture and lists fitting ones as tasks. A plain UI works where paper and digital coexist, returning time to face-to-face support.
2025F
Award of Excellence

FutureRun

第3回 AI Agent Hackathon with Google Cloud
An app for experiencing race day before it arrives. It cross-references the course GPX, the weather and the runner's goals and training history, then works out which points to watch, how to pace and where to drink. The advice comes back as a generated video with captions, helping runners picture the course and judge well.
2025P
Award of Excellence

PawMate

第3回 AI Agent Hackathon with Google Cloud
A web service linking the owner of a lost pet with whoever spots it. One agent reads images, another predicts behaviour, and together they estimate from weather, time of day and terrain where the animal is likely to be, drawing it as a heat map. Finders' photos are auto-matched by similarity, and both sides can chat directly.
2025R
Award of Excellence

RouteKeeperAI

第3回 AI Agent Hackathon with Google Cloud
A system that surfaces road hazards before you drive them. It pulls Street View imagery every 50 metres along a chosen route and has AI analyse each point from several angles — blind corners, road surface, visibility — scoring risk on a ten-point scale. The result is a colour-coded map you can question spot by spot in chat.

See all winners of 第3回 AI Agent Hackathon with Google Cloud →

Winners using the same tech

Check the original

The links below lead to external sites.

Summaries are written by this site. Project pages include demo videos, screenshots and the team's own write-up (videos may autoplay).