Thanks for sharing. Googling for "SCRIPT/VS" gives the only link pointing to somewhere in the middle of IBM's z/OS manual. Must be a lost alien technology by now.
There's a Wikipedia page[1] which covers the general background and a copy of the SCRIPT/VS Text Programmer's Guide[2] (which was my bible back in the day) on archive.org, which should give you a pretty good overview.
[1] https://en.wikipedia.org/wiki/SCRIPT_(markup) [2] https://archive.org/details/bitsavers_ibm370DCFSpositionFaci...