code: def _get_build_type(fnames, samples, caller):
      
      build_type = set()
      if any(vcfutils.vcf_has_variants(f) for f in fnames) and caller not in NO_DB_CALLERS:
          for data in samples:
              if any([x in dd.get_tools_on(data)
                      for x in ["gemini", "gemini_orig", "gemini_allvariants", "vcf2db_expand"]]):
                  if vcfanno.annotate_gemini(data):
                      build_type.add("gemini_orig" if "gemini_orig" in dd.get_tools_on(data) else "gemini")
                  else:
                      logger.info("Not running gemini, input data not found: %s" % dd.get_sample_name(data))
              else:
                  logger.info("Not running gemini, not configured in tools_on: %s" % dd.get_sample_name(data))
      else:
          logger.info("Not running gemini, no samples with variants found: %s" %
                      (", ".join([dd.get_sample_name(d) for d in samples])))
      return build_type
docs: Confirm we should build a gemini database: need gemini in tools_on.
  
      Checks for valid conditions for running a database and gemini or gemini_orig
      configured in tools on.