Problems / Multi-agent and harness, medium
A concierge agent calls a booking agent, which calls an airline’s agent over A2A (40 slots, about 4 s a request). Both callers time out after 8 s and retry twice at once. At 15 s bookings jump 2.5× for 10 seconds.
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Success ≥ 95%, p99 ≤ 30 s.
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 3; 1 of them are hidden until then.
6 requests a second for 45 seconds: 100% booking (writes).
What each component does in this design, and what calls it. The simulator mimics each one from these settings.
| Component | Its job here | Settings |
|---|---|---|
| Load balancerLoad balancer | Traffic enters here.Calls Concierge agent (A).Layer 4 balancers route by IP and port; layer 7 balancers read HTTP and can route by path or header. | – |
| Concierge agent (A)App service | Load balancer forwards to it.Calls Booking agent (B).Little's law: throughput ≈ concurrency ÷ latency. 200 slots at 50 ms serve about 4,000 req/s. | 3 replicas × 500 slots · timeout 8.0 s |
| Booking agent (B)App service | Concierge agent (A) calls it.Calls Airline agent (C, over A2A).Little's law: throughput ≈ concurrency ÷ latency. 200 slots at 50 ms serve about 4,000 req/s. | 3 replicas × 500 slots · timeout 8.0 s |
| Airline agent (C, over A2A)A2A agent endpoint | Booking agent (B) calls it.Agent-to-agent protocols let agents from different teams or vendors hand work to each other. | 40 slots · 3,000 calls/min |