Use direct agents for sprints. Use Millrace for marathons.
Direct coding agents can win sprints: small, local, well-scoped edits where a human can keep context in their head and judge the result immediately. Millrace governs marathons: work that must survive restarts, accumulate evidence, move through stages, and close under operator control.
Use Millrace when the operating problem is bigger than the edit.
Millrace earns its complexity when work has to keep moving without relying on a single chat transcript. The runtime owns state, dispatch, evidence, recovery, and the final closure gate while agents do bounded stage work.
When Millrace owns state, the operator gets a recoverable system.
Work stops being a fragile conversation. Queue records, compiled plans, active stages, artifacts, and closure evidence become the source of truth. Agents can still win sprints inside a stage, but Millrace governs marathons by deciding what runs next and whether the evidence is strong enough to close.