You can ask the agent to check that it doesn't leave a database instance exposed to the public, and present you with proof for you to check (references to the code and the relevant Cloudformation documentation). Then repeat this for all the things you'd normally want to check for in a code review.
In that case I'm just moving the reading of the documentation from reading it as I'm writing the yaml to when I'm doing a code review. Not saying it isn't helpful to have a pair researcher, just seems like I'm moving things around .