client: {
    mandatory: {
        KeypadInput: .;
        MediaPlayback: .;
        OnOff: .;
    };
    optional: {
        AccountLogin: .;
        ApplicationLauncher: .;
        AudioOutput: .;
        Channel: .;
        ContentControl: .;
        ContentLauncher: .;
        LevelControl: .;
        LowPower: .;
        MediaInput: .;
        TargetNavigator: .;
        WakeOnLan: .;
    };
}

A definition for each client cluster supported by the endpoint per the Matter specification.