The cost centre in this operating model is tokens, not synthetic headcount. That means we maximise affordable breadth in junior lanes and preserve senior-tier reasoning for hard, expensive decisions.
Mid-tier agents carry most day-to-day implementation. Senior roles handle exception paths, architectural trade-offs, and final acceptance gates. This keeps cycle time fast without flooding frontier spend across routine work.
The real failure mode
The economic failure mode is not many agents; it is spending top-tier reasoning on work that should have been delegated, reviewed, and escalated only when needed. Tier discipline is a quality-control strategy as much as a finance strategy.
Governance, not model choice
Teams that skip this discipline often blame model quality when the true issue is governance: they run premium judgement at every stage and remove the review boundaries that would have caught defects earlier, at lower cost.