Six Sigma DMAIC and DMADV are probably good agent loops;

> DMAIC stands for Define, Measure, Analyze, Improve, and Control

> DMADV (Define, Measure, Analyze, Design, Verify)

Lean Six Sigma: https://en.wikipedia.org/wiki/Lean_Six_Sigma :

DOWNTIME (Defects, Over Production, Waiting, Non-used Talent, Transportation, Inventory, Motion, Extra-processing)