IDF is used to measure how important a word it is (common or rare). In other words, it is a measurement score of word popularity. TF-IDF can measure the document relevancy for a given word. Can we directly use it as the score of “Terms Match”?
For others, to complement the infos of your post:
And I think you are right. TF-IDF sounds like a good candidate tom compute the “terms match” part of the score