Are commas necessary between coordinate adjectives? [duplicate]
Here's how I would word the sentence fragment (which I've turned into a full-blown sentence:
To reach a mutually agreed upon, long-term, comprehensive solution which would ensure Iran's nuclear program will be exclusively peaceful, is a worthy goal for the latest round of talks initiated by Slovenia.
The way in which I've punctuated the sentence illustrates how the rules apply in a situation such as this.