Command Input uses macOS Accessibility APIs and a CoreGraphics event tap (CGEventTap) to detect standalone Left and Right Command key presses. This document states what that tap does and does not do.

• All keyDown and keyUp events are observed. The tap must see every key-down and key-up so that pressing a combination such as Command-A or releasing a non-modifier key while Command is held cancels a pending input-mode switch. Without that, releasing Command after a shortcut would be mistaken for a standalone tap and would emit Eisu or Kana. Neither mask can be removed without changing that behavior.
• Keystrokes are not stored. Modifier state lives in memory only for the duration of a press, then is discarded. Nothing is written to disk, logs, or temporary files.
• Keystrokes are not transmitted. The app contains no networking code, analytics, or telemetry. The only process it launches is /usr/bin/open, used to reopen the app after Restart and to open System Settings.

The event tap is created with CGEventTapOptions.listenOnly. That option prevents the tap from modifying or suppressing events. It does not prevent observation. "Listen-only" is proof that Command Input does not rewrite or drop your keystrokes; it is not proof that it cannot see them.

Accessibility permission is still required. A listen-only tap that watches keyDown and keyUp is still a keystroke observer.

• Event handling is confined to Sources/App/KeyRemapper.swift and Sources/Core/KeyRemapEngine.swift.
• The app imports Cocoa, SwiftUI, Observation, and ServiceManagement. It does not import Network, use URLSession, or open sockets.

From a clone of this repository:

# Should print nothing.
rg 'URLSession|Network|NWConnection|socket|http://|https://' Sources/

Read Sources/App/KeyRemapper.swift and Sources/Core/KeyRemapEngine.swift end to end. Together, the two files are roughly 250 lines and contain the entire event-tap and remapping path.

Do not open a public issue for a security vulnerability.

1. Use GitHub Private Vulnerability Reporting.
2. Include steps to reproduce and any relevant system logs.
3. We will acknowledge the report and give an estimated timeline for a fix.