A participant in a LocalDown hackathon built Wei, an AI agent for habit-building, and won 3rd place.Wei is an AI agent that makes habit-building effortless through natural dialogue and offers rewarding experiences.The tutorial covers building Wei from scratch using the official OpenAI Agents Python SDK and AI Agents SDK.Wei is powered by tools like shadcn/ui for Next.js, motion-primitives, and prompt-kit.Approximately 6 to 7 AI Agents handle different aspects of the app, transferring control to each other as needed.Agents like Greeter, General, Rewards, Points, Habits, and Info Agents manage various functionalities in Wei.Functions such as getting user data, managing habits, calculating points, and providing rewards are handled by specific agents.The API logic for Wei involves handling requests, managing database functions, and using cached user data for efficient processing.UI components like ChatInterface, ChatInput, and associated contexts are crucial for enabling interactions with the AI agent.The tutorial delves into building the app's UI/UX, running the app locally, and deploying it using Vercel.