See agreement in the Glossary, defined as:

An Agreement is created from an Offer when agents have accepted all of the mandatory roles of the Offer.

• RegenCHOICE → fit

aSimonG: There's an apparent distinction between an agreement made on the basis of one offer, accepted by another agent, and a RegenCHOICE-style fit when the requirements of each enquiry are fulfilled by the other enquiry.