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chini-011-cafe-morning-rush

Cafe Morning Rush

One espresso machine, two baristas, a line out the door, and the milk steamer just died.

Source: Operations research, queueing theory, every barista who has ever worked a 7am shift

Prompt

Design the workflow for a small specialty cafe handling a 7am-9am rush.

Functional:
- Customers arrive at the register, place an order, and either take it to-go or sit down.
- Orders are routed to the bar (espresso drinks) or the kitchen pass (pastries, sandwiches).
- Drinks require the espresso machine (single shared resource) and a milk steamer for anything with milk.
- Completed orders are called out by name and handed off.

Non-functional:
- A 4x arrival burst at 8am must not cause customers to walk out (drop rate kept low).
- If the milk steamer fails mid-rush, milk drinks must reroute to a backup steamer or be politely refused before money changes hands. The shop cannot just stop serving.
- The single espresso machine must not become the bottleneck that backs up the entire queue. Batch where possible.

Return a Chinilla CanvasState. Components are people, machines, and physical stations. Behaviors are still the same primitives: queue (the line), retry (re-pull a bad shot), ratelimit (cap drink complexity at peak), circuitbreaker (steamer failover), storage (pastry case), split (drink vs food routing).

Constraints

Max components
12
Required behaviors
queue, circuitbreaker, split
Monthly budget
$18000

Stress scenarios

Steady morning

baseline

Normal arrival rate, no failures. Most orders are drinks, some food.

8am rush

spike

Arrival rate quadruples for the peak window. Line should not collapse.

Milk steamer fails

outage

Primary steamer dies mid-rush. Milk drinks must reroute or be rejected at order time.

Espresso machine warming up

latency

Espresso machine takes longer than usual per shot. Bar must absorb without backing up the register.

Pass criteria (overall)

Min stability score
65
Max drop rate
8.0%
Min delivery rate
88.0%
Max errors
6

Submit your run

Submissions go through the chini-bench CLI. It calls your model with your key, scores the result locally, and posts to the leaderboard. Nothing leaves your machine except the canvas it produces.

End-to-end:
pip install git+https://github.com/collapseindex/chini-bench-cli.git
export OPENROUTER_API_KEY=...

chini-bench run chini-011-cafe-morning-rush \
  --provider openrouter --model google/gemini-2.0-flash-001 \
  --as alice --x alice --linkedin alice-builds
Or inspect the prompt first:
chini-bench prompt chini-011-cafe-morning-rush
Providers: openai · anthropic · google · openrouter · ollama

Leaderboard

Rank Submitter Model Score Stability Delivery Design Pass Links
#1 alex default
A anthropic/claude-sonnet-4.6
90 78.0 100.0 100.0 X
#2 alex default
X x-ai/grok-4.20
89 75.0 100.0 100.0 X
#3 alex default
O openai/gpt-5.4
89 82.0 100.0 100.0 X
#4 alex default
G google/gemini-3.1-pro-preview
68 49.0 73.0 100.0 X
Per-scenario breakdown of the top run
Scenario Health Drop rate Delivered Pass
baseline 80.0 0.3% 485
eight-am-spike 75.0 0.4% 1783
steamer-down 76.0 0.0% 276
slow-machine 81.0 0.3% 447