Problems / Agents and tools, easy

MCP gateway quota

Every tool call goes through an MCP gateway (auth, allow-lists, quotas) limited to 600 calls a minute. Agents make about 18 tool calls a second.

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Your goals

Success ≥ 95% of tasks, p99 ≤ 90 s.

The traffic

3 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 Model, MCP gateway.An agent loops: think, call a tool, read the result, repeat until done.400 slots · 6 steps
ModelLLM endpointAgent orchestrator calls it.Latency has two parts: time to the first token, then a steady stream of tokens per second.300 streams
MCP gatewayMCP gatewayAgent orchestrator calls it.Calls MCP tool servers.MCP (Model Context Protocol) is an open standard for connecting models to tools and data.2000 slots · 600 calls/min
MCP tool serversTool / MCP serverMCP gateway calls it.Tools give the model actions such as search or database queries; each call is another round trip.200 slots

Hints

Try it first. Open one hint at a time if you get stuck.

Hint 1

18 × 60 ≈ 1,080 calls a minute.

Hint 2

Look for 429s on the gateway.

One way to solve it

Raise the MCP gateway quota.

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