Building RehearsAI for the Gemini Live Agent Challenge

A few weeks ago we came across the Gemini Live Agent Challenge, a Google hackathon focused on building real-time AI agents with Gemini. We were immediately interested — we had been experimenting with text-based AI apps for a while, but we had always wanted to build something with live agents. At first we explored a few ideas around language learning, but eventually we landed on something that felt much more personal: Rehearse AI . Rehearse AI is an app designed to help people practice difficult conversations. You can simulate a conversation with an AI agent, rewind the timeline, try different responses, and explore how the conversation could unfold depending on what you say. The idea is simple: practice the conversation before it happens in real life — so when the moment comes, you’re ready. We started prototyping the project in Google AI Studio and built the app using Gemini models , the Google AI SDK , and React . One of the biggest challenges was designing the conversation timeline