Vercel Labs’ agent-desktop is a Rust CLI and C library for reading and operating macOS, Windows, and Linux applications through OS accessibility trees. A snapshot returns JSON and element references; the agent acts on a reference and observes again. Default accessibility actions do not take the pointer or focus. Stale or ambiguous references produce errors and require a fresh snapshot. Requirements include macOS Accessibility permission and a Linux graphical session, with capabilities varying by platform. The Apache-2.0 tool leaves the reasoning loop to the agent and does not guarantee compatibility with every application.