CC2642R: Service User Description UUID ?

is it a way to add a description to a service entry as for caracteristics one ?? 

this is working for naming correctly a custom define caracteristic

 // TX Characteristic Declaration
    {
      { ATT_BT_UUID_SIZE, characterUUID },
      GATT_PERMIT_READ,
      0,
      &NUS_TXProps
    },
      // TX Characteristic Value
      {
        { ATT_UUID_SIZE, NUS_TXUUID },
        GATT_PERMIT_WRITE,
        0,
        NUS_TXVal
      },
      // TX Characteristic User Description
      {
        { ATT_BT_UUID_SIZE, charUserDescUUID },
        GATT_PERMIT_READ,
        0,
        NUS_TXUsrDesc
      },

but if I try for service declaration it has no effect 

// NUS Service Declaration
{
{ ATT_BT_UUID_SIZE, primaryServiceUUID },
GATT_PERMIT_READ,
0,
(uint8_t *)&NUSDecl
},
// Service Characteristic User Description
{
{ ATT_BT_UUID_SIZE, charUserDescUUID },
GATT_PERMIT_READ,
0,
NUS_ServUsrDesc
},

said differently 

is it a way to named a custom service with unknown UUID

thanks for your help