Coordinate adjectives are adjectives that modify the same noun independently and can be separated by "and" or rearranged without changing the meaning of the sentence. A typical example of a sentence containing coordinate adjectives would be:
"The tall, slender man walked into the room."
In this example, "tall" and "slender" are coordinate adjectives describing "man" and should be separated by a comma.
If you provide a specific sentence, I can help identify if it contains coordinate adjectives that need commas!