$ gemmi validate -h
Usage: gemmi validate [options] FILE [...]

Options:
  -h, --help      Print usage and exit.
  -V, --version   Print version and exit.
  -v, --verbose   Verbose output.
  -q, --quiet     Show only errors.
  -f, --fast      Syntax-only check.
  -s, --stat      Show token statistics
  -d, --ddl=PATH  DDL for validation.
  --no-regex      Skip regex checking (when using DDL2)
  --no-mandatory  Skip checking if mandatory tags are present.
  -p              Check if parent items (DDL2) are present.
  -m, --monomer   Extra checks for Refmac dictionary files.