The terms agreed cover: the objective and the scope; what the practitioner is responsible for; a statement that the work follows AICPA attestation standards; what the responsible party must do and, if it is separate, what the engaging party must do; the inherent limits of an examination; the criteria; and the engaging party's agreement to supply a representation letter when the work ends.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.