GAINs and HCINs give you two shapes for a multi-agent workflow: the flat network and the tiered one. This is a practical guide to designing with them, updated against the contemporary, verified evidence — including the most important rule, which is knowing when not to build a network at all.
Step 0 — Should this be a network?
Start here, because the seductive failure is reaching for agents because it sounds powerful. A network multiplies token cost by roughly an order of magnitude and adds a failure surface at every seam; the largest study of multi-agent failures (MAST) found high
