Problems / Multi-agent and harness, medium

Multi-agent token bill

Every subagent sends 3,000 tokens of context. Eight subagents per question multiply token use past the provider quota.

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Your goals

Success ≥ 95% of tasks, p99 ≤ 90 s.

Test cases

Like a coding problem, a solution has to pass every case, not just the one it was built for. Submit in the lab runs all 6; 2 of them are hidden until then.

  1. As given. The problem’s own traffic, scheduled failures and seed.
  2. Peak hour. 25% more traffic than the problem states, with the same failures.
  3. A slow dependency. The main data store or model answers twice as slowly for part of the run.
  4. A server dies. One replica of the service with the most replicas is killed for part of the run.

The traffic

2 requests a second for 45 seconds: 100% task (writes).

The system

What each component does in this design, and what calls it. The simulator mimics each one from these settings.

ComponentIts job hereSettings
Load balancerLoad balancerTraffic enters here.Calls Agent API.Layer 4 balancers route by IP and port; layer 7 balancers read HTTP and can route by path or header.–
Agent APIApp serviceLoad balancer forwards to it.Calls Agent orchestrator.Little's law: throughput ≈ concurrency ÷ latency. 200 slots at 50 ms serve about 4,000 req/s.3 replicas × 500 slots · timeout 180 s
Agent orchestratorAgent orchestratorAgent API calls it.Calls Subagent pool.An agent loops: think, call a tool, read the result, repeat until done.400 slots · 1 steps
Subagent poolSubagent poolAgent orchestrator calls it.Calls Model.Multi-agent research systems fan a task out to parallel subagents and use many times more tokens than a single agent.400 slots · 8 steps
ModelLLM endpointSubagent pool calls it.Latency has two parts: time to the first token, then a steady stream of tokens per second.300 streams · 2M input tokens/min

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