Add Comma After “official” in “official third-party documentation”?

Question

I'm drafting an internal standard on internal documentation covering third-party products or services in my organization.

Documentation covering third-party products or services SHOULD NOT:

• Include specific details or information already covered in official third-party documentation—to avoid plagiarism or the spread of misinformation when official third-party documentation is updated and internal documentation is not

One of my team members submitted an edit to change:

official third-party documentation

To:

official, third-party documentation

I disagreed with him—my argument being that "official" in this context is an adjective and adding a comma would change the meaning.

Should I add a comma after the word "official" in "official third-party documentation"?

Answer 1

There are two adjectives in this phrase that modify the word documentation: official and third-party. If they are coordinating adjectives, a comma is required. If they are cumulative adjectives, no comma is necessary.

There are two tests to determine if adjectives before a noun are coordinating adjectives:

1. Can you replace such a comma with the coordinating conjunction "and"?
2. Can you flip the adjectives without altering the meaning?

In this case, "third-party, official documentation" doesn't work. It suggests that third-party documentation is its own thing, like fire truck or Christmas tree. The adjectives are, then, cumulative adjectives, and no comma is required (see Commas with Adjectives).