the link for kasyan's indesign comparing script is https://creativepro.com/scr…..encing.php
so far as comparing a pdf to an indesign file which may have created it, could make a new indesign file and run the multipageimporter2.2.1.jsx to import the pdf into that file; and then compare the two using kasyan's script. read the link to see how the differences between the two files appear.
my workplace has an SOP that ANY artwork with hard copy supplied MUST BE overlaid to our proof to ensure that linebreaks are consistent, amongst other things. however, that falls in a heap when the hard copy:
* isn't to scale;
* isn't the latest version (i.e. type alts have been done);
* is double sided (can't see through the hard copy properly).
mind you, the customers that DO supply proofs normally supply pdfs of their art anyway (no native files) and rarely have problems.
i might add that supplying hard copy is still a good idea, it gives the prepress people like myself some comparison to the artwork the RIP produced, and given that we haven't seen the artwork before, won't be aware if images have dropped off, etc.