GARDE-Chat is an AI-powered, no-code platform that enables researchers to build chatbot-based digital health interventions at scale. Developed by Professors Guilherme Del Fiol and Ken Kawamoto, the tool supports rule-based and LLM-driven chatbots and has already powered more than 15 projects—including large trials reaching up to 100,000 patients. By improving access to evidence-based services and helping secure over $35 million in federal funding, GARDE-Chat demonstrates how AI can make healthcare interventions more scalable, effective, and widely accessible.