The assignment asks you to review the brief in two ways. In the first review, you can be as critical and unhelpful as you wish. Find as many faults as you can in the brief and tell the author in blunt, even unsympathetic, terms where s/he has blown it.
In the second review, try to present your criticisms in as helpful a manner as possible. Note the positive aspects of the brief and phrase your criticisms with specific comments that are targeted at the brief instead of the author.
When finished, discuss the two critiques. List the strategies for review that you think would be the most helpful if it was your paper under the microscope. If you can think of any additional strategies, share them with your classmates.