server: {
    mandatory: {
        MicrowaveOvenControl: typeof MicrowaveOvenControlServer;
        MicrowaveOvenMode: typeof MicrowaveOvenModeServer;
        OperationalState: Type<WithAlterations<OperationalState.Cluster, {
            attributes: {
                countdownTime: {
                    optional: false;
                };
            };
        }>, typeof OperationalStateServer, OperationalStateInterface>;
    };
    optional: {
        FanControl: typeof FanControlServer;
        Identify: typeof IdentifyServer;
    };
} = ...

An implementation for each server cluster supported by the endpoint per the Matter specification.