A capability registry has three agents that all match the required task class. Agent A has current_load=2, max_concurrent=10. Agent B has current_load=8, max_concurrent=10. Agent C has current_load=1, max_concurrent=5. The tiebreaker should select which agent?
Answer: Agent C, because it has the lowest load ratio (20%) relative to its capacity
Load ratio (current_load / max_concurrent) is the correct tiebreaker because it normalizes load across agents with different capacity limits. Agent A has ratio 0.20 (2/10), Agent B has 0.80 (8/10), Agent C has 0.20 (1/5). Agents A and C are tied on load ratio. At that point, Agent C's lower absolute load (1 vs. 2) is the secondary tiebreaker — though C also has lower total capacity, meaning a single additional request has more relative impact. In practice, load ratio is the primary signal; absolute remaining capacity is secondary. Agent B's high load ratio (0.80) makes it the worst choice regardless of demonstrated throughput — it is near saturation.