The roommate agreement is a document that binds up to four (4) roommates into a lease agreement where each individual is responsible to come up with their money for the rent payment every month. In addition, the form usually has other bills every month such as cable, electricity, internet, and others that must be split between the roommates.
This form is not to be signed by the landlord. It is to be agreed upon between the roommates (with usually one of the individuals signed to a lease with the landlord separately).