def _parse_tool_line(line: str) -> str:
    """
    Return ``True`` if this line contains a tool preamble of
    the format we add in the converter scripts.

    >>> _parse_tool_line("# ALIGNMENT TOOL cross_match")
    'cross_match'
    >>> _parse_tool_line("# Something else")
    ''
    """
    if line.strip().upper().startswith("# ALIGNMENT TOOL"):
        return " ".join(line.strip().split()[3:])
    else:
        return ""