AgentStudio is an open-source toolkit that covers the entire life cycle of building general-purpose virtual assistants. It provides environment implementations, benchmark suites, data collection pipelines, and a graphical interface to promote the development of future research on general-purpose virtual assistants. AgentStudio provides a unified observation and action space consistent with human-computer interaction, allowing for the evaluation of agents and data collection on any task a human can perform. This feature greatly expands the potential task space. Therefore, AgentStudio can promote the development and evaluation of agents capable of spanning a variety of real-world use cases.