$ gemmi tags -h
Usage:
 gemmi tags [options] FILE_OR_DIR[...]
List CIF tags with counts of blocks and values.
  -h, --help     Print usage and exit.
  -V, --version  Print version and exit.
  -v, --verbose  Verbose output.
  --count-files  Count files instead of blocks.
  --glob=GLOB    Process files matching glob pattern.

Options for making https://project-gemmi.github.io/pdb-stats/tags.html
  --full         Gather data for tags.html
  --entries-idx  Use entries.idx to read more recent entries first.
  --sf           (for use with --entries-idx) Read SF mmCIF files.
