{
  "passed": [
    "All 740 objective answer keys score 4/4; public exercise DTOs omit keys and written solutions.",
    "Structured AI feedback contract, reference solution, rubric totals, invalid scores, provider errors, and incomplete responses.",
    "Independent regression fixtures: linear, quadratic, exponential, zero variance, and invalid input.",
    "Guest objective access blocked and validation: stale content, malformed answers, written authentication, cross-origin, and request size.",
    "Login and submitted-details gates, persisted registration, existing account authentication, owned-student isolation, saved scores, replay idempotency, conflicting replays, and progress retrieval.",
    "Persistent atomic rate limit rejects requests above the configured limit."
  ],
  "liveOpenAI": "Provider behavior tested with fixtures; no paid API calls.",
  "visualBrowser": "Unavailable: browser URL verification policy stopped Computer Use."
}