Prelude Health is a patient-facing AI web app that lets users chat with an intelligent assistant to schedule appointments with semantically matched specialists, then seamlessly switch to a voice phone call mid-conversation with full context retained. The assistant collects patient information conversationally, checks real-time doctor availability across five specialties, books appointments, and automatically sends confirmation emails and SMS notifications. Patients can also request prescription refills and get office information like hours and addresses, all through natural language over chat or voice.