/sys$common/syshlp/helplib.hlb DEFINE, /CHARACTERISTIC, Parameters  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 characteristic-name

    Assigns a name to the characteristic being defined. The
    characteristic name can be the name of an existing characteristic
    or a string of 1 to 31 characters that defines a new
    characteristic. The character string can include any uppercase
    and lowercase letters, digits, the dollar sign ($),  and the
    underscore (_),  and must include at least one alphabetic
    character. Only one characteristic name can be defined to each
    number.

 characteristic-number

    Assigns a number in the range 0 to 127 to the characteristic
    being defined.