diff --git a/src/lammps.cpp b/src/lammps.cpp
index ea83dccad1..9e340477f4 100644
--- a/src/lammps.cpp
+++ b/src/lammps.cpp
@@ -1142,6 +1142,7 @@ void _noopt LAMMPS::help()
           "-in none/filename           : read input from file or stdin (default) (-i)\n"
           "-kokkos on/off ...          : turn KOKKOS mode on or off (-k)\n"
           "-log none/filename          : where to send log output (-l)\n"
+          "-mdi '<mdi flags>'          : pass flags to the MolSSI Driver Interface\n"
           "-mpicolor color             : which exe in a multi-exe mpirun cmd (-m)\n"
           "-cite                       : select citation reminder style (-c)\n"
           "-nocite                     : disable citation reminder (-nc)\n"