Are your referring to the section “8.6.4 Moltemplate Tutorial”?
Indeed, those settings are not explicitly mentioned in the tutorial. The reason is that the tutorial focuses on how to use Moltemplate to create a complete input deck for a LAMMPS simulation, including the DATA file.
Specifically, the OPLS-AA settings are inherited from the file oplsaa.lt but not reported in the manual. However, you will find them in the .init file.
Cheers,
Otello