CM-Agent

Hello everyone, Regarding the CM delivery method, there are 3 concepts explained in the AHPP: (1) CM-Agent (2) CM-Adviser (CMa) (3) CM-Constructor (CMc/CMaR) Except CM-Agent, both CM-Adviser and CM-Constructor have cast in AIA Agreements with the owner, C132 and C133, respectively. CM-Agent has a "consultancy" role with the owner for a fixed fee, with or without a defined SoW, and I couldn't find any verbiage indicating an AIA Document that the owner signs with the CM-Agent. However, while viewing the AIA Document families, I came across AIA Document C103-2015, Standard Form of Agreement between Owner and Consultant without a Predefined Scope of Consultant's Services. Could this document be used for CM-Agent, or, since CM-Agent's services are much like those of a CM-Adviser, is it more logical (or practical) to use a "modified" AIA C132-2019 instead? I greatly appreciate your thoughts.