app_appearance

This tool on every surface: CLI · MCP · Python · JavaScript · Go · Java · .NET

Read the device's light/dark setting, or change it. Call with no argument to read. Dark mode renders every screen differently and is where contrast and hard-coded colors break, so it is worth checking a flow in both. Android also accepts "auto"; iOS does not and says so. Changing it invalidates the refs from the previous screen.

Changes the device, the app or the session: readOnlyHint is false.

Arguments

Name	Type	Required	What it is
appearance	string: light, dark, auto		"light", "dark", or "auto" (Android only). Omit to read the current setting.
device	string		Device serial to target, e.g. "emulator-5554". Omit when only one device is running.
driver	string: uiautomator2, uiautomator, wda		Driver to use: "uiautomator2" (default for Android; fast, installs a server APK on first use), "uiautomator" (Android, installs nothing, slower, cannot type), or "wda" (WebDriverAgent: iOS simulators and iPhones).

Examples

Each is the arguments of a tools/call request; the first is shown whole.

Switch to dark mode

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "app_appearance",
    "arguments": {
      "appearance": "dark"
    }
  }
}

On an Android 15 emulator the answer's text was:

dark (was light)

mobium appearance dark on an Android 15 emulator