GlobalActionTool

global_action — dispatch a system-wide AccessibilityService global action: back, home, recents, notifications, quick_settings, power_dialog, lock_screen, or screenshot (see the companion MAP).

The action string is lowercased before lookup. AccessibilityTools.idempotentGlobalActions lists the subset dispatchers may mark as safe to retry.

Params: required action.

On success returns success = true and the resolved action name. Errors are long-form messages: action is required, an "Unknown action" message listing the valid keys, the notConnectedError message when the service is not bound, and a "performGlobalAction returned false" message when the system rejects the action.