How the macOS accessibility tree works

Silent educational animation. All diagrams are illustrative; no live desktop was inspected.

Opening: Lattices / Field Guide. THE ACCESSIBILITY TREE. Your apps have a second interface. AX is what an app tells tools about its buttons and windows.

[0–8 seconds] You see a window and an Export button. Accessibility, often shortened to AX, describes those controls to other tools.

[8–16 seconds] That description is a tree. An app contains a window. The window contains controls, such as buttons.

[16–26 seconds] An element can expose its role: Button; its title: Export; and a supported action: Press. A tool can ask the app to press it.

[26–36 seconds] The app decides what it exposes. Some controls may be missing or incomplete. Tools need Accessibility permission to access and control other apps.

On-screen diagram labels: Illustrated app; Export; What you see on screen; App; Window; Export button; The button tells a tool; What am I?; Role: Button; Title: Export; Action: Press; Only what this app exposes.

Footer: Lattices / Field Guide. Illustrative diagram · not a live desktop inspection. lattices.dev/learn.