AI Research Scientist (Multimodal post-training)

At Sword, we’re building AI to heal billions and unlock humanity’s full potential. In doing so, we’re pioneering AI Care, a fundamentally new approach to healthcare built for medical reasoning, safety, and real-time treatment, not generic technology applied after the fact. As both a clinical-centric frontier AI lab and an applied AI platform, Sword is reimagining how care is delivered at scale, removing traditional barriers like appointments, waiting rooms, and stigma so more people can access the care they need—and ultimately get back to lives lived in full. Since 2020, Sword has expanded across physical therapy, women’s health, cardiometabolic, and mental health, and is now moving beyond the session to a fully AI-native, 24/7 care program that brings physical activity, therapeutic exercise, psychotherapy, nutrition, and behavior change into one connected experience. More than 700,000 members across three continents have completed over 10 million AI sessions, helping 1,000+ enterprise clients avoid more than $1 billion in unnecessary healthcare costs. Backed by 42 clinical studies, 44+ patents, and more than $500 million raised from leading investors including Khosla Ventures, General Catalyst, and Founders Fund, Sword is defining a new standard for healthcare. Role   At Sword, we operate as both a clinical-centric frontier AI lab and an applied AI platform — conducting the foundational research that makes clinical AI possible, then putting it into practice through platforms that treat patients directly. Our AI Research team builds the core intelligence behind Dawn and Phoenix, our continuous, always-on care agent.   Healthcare demands AI that goes far beyond answering questions or completing tasks. It requires systems capable of sustained engagement across dozens of interactions — understanding a patient's history, perceiving their present state, and guiding their recovery over weeks and months. Delivering care at this level means AI must see, hear, and understand patients across modalities.    To make this possible, we are pushing the boundaries of multimodal perception — fusing video, language, and speech into unified patient understanding — alongside memory systems and multi-turn reinforcement learning for long-horizon treatment planning. We are building a category of AI product that has never existed before — AI that provides real clinical care autonomously, at scale. That means operating at the frontier of both research and product development simultaneously, often without a playbook. You will thrive here if you are energized by uncertainty, comfortable making high-stakes decisions with incomplete information, and motivated by the outsized impact that comes with pioneering something genuinely new. It's high pressure, high reward — and the team that does it best.   Our researchers don't choose between scientific rigor and product impact. The team actively publishes in top-tier AI conferences and clinical journals while shipping the models that power care for hundreds of thousands of patients. We have the computer, the data, and the team to support your best work. What you’ll be doing: What you need to have: What we would love to see: