core practice · system design prompt
Design exercise: Tracing & Replay
Deterministic inputs, event logs, snapshots, prompt/model versions, tool fixtures, and counterfactual re-execution. Implement designOutline() returning non-empty values for: capturedInputs, versionPins, replayMode. Each value must name a concrete mechanism or decision.
The mechanism
Replay requires capturing every non-deterministic dependency: model and prompt version, context, tool results, random seeds where available, and state transitions.
Expected evidence
A design outline with capturedInputs, versionPins, replayMode plus an explicit failure mode or trade-off.
Try this drill in the practice workspace →
Hints when you need them
- Name the failure mode before selecting the mechanism.