Explanation

Understand the design ideas behind Cua and how its main pieces fit together.

Explanation is for the parts of Cua that are easier to use once the model is clear. These pages are not recipes or API listings. They describe the concepts, constraints, and tradeoffs behind Cua's two main ways of giving an agent a computer: driving an existing machine with Cua Driver, or running an isolated cloud desktop with Cua Sandbox. Read this section when you want to understand why the system behaves the way it does, what guarantees it is trying to preserve, and where each component sits in the stack.

The section starts with What is computer use?, which defines computer-use agents and where Cua fits. The no foreground contract explains the central invariant in Cua Driver: agent actions must not steal focus, move the real pointer, or interrupt the person using the machine. Process model describes how Cua Driver runs as an MCP stdio server, daemon, and CLI. How sandboxes work covers cloud desktop sandboxes, their lifecycle, and snapshots. Architecture ties the pieces together: Cua Driver, Cua Sandbox, and the computer-server.