This addon generates a hash value (MD5) for the selected field. Each field is processed and stripped of punctuation, pronouns, whitespace, etc... The checksum is used to search for duplicates in other notes/models that may have a different structure.
So, to illustrate:
"My ball.", "my balls!", "your ball?", "Your balls...", "Johny's Ball"
Except for the last one, the first four are all duplicates after processing.
You may also need these additional addons in order to manage the tags:
Hierarchical Tags: https://ankiweb.net/shared/download/1089921461
Using regexps to remove tags: https://ankiweb.net/shared/info/1502698883
Porter2-stemmer by Evan Dempsey, https://github.com/evandempsey/porter2-stemmer
Made using Wordsworth's skeleton code: https://github.com/lovac42/Wordsworth