Project Solara is Microsoft’s early chip-to-cloud platform for agent-first devices, built to support a future where agents are easy to reach, naturally engaged, and always available across new device form factors. Instead of centering the experience around traditional apps, Project Solara is designed for an open, multi-agent world where specialized agents can be built, deployed, and experienced across every layer of the stack. Microsoft imagines a diverse ecosystem of agent-first devices, from small to large, fixed to hypermobile, and personal to professional, each supported by a base OS, shell, developer ecosystem, apps, web-based intermediation, and silicon integration. It is designed to make agents more capable and accessible by composing hardware, software, cloud services, and developer tools into a foundation for new interaction patterns. Project Solara includes two concept devices that show how agent-first computing could work in practice.