{
  "panel": "provider_vintage",
  "provider": "glm",
  "provider_cutoff": "2023-03-10",
  "cutoff_provenance": "empirical-probe-v1 (dual-blind dated-event ladder; NOT a vendor declaration) — frozen in config/e3_live_contracts.yaml",
  "block_on_unknown": true,
  "probe_artifact": {
    "model": "glm-4.7-flash",
    "boundary": {
      "latest_known": "2023-03-10",
      "earliest_unknown": "2024-11-06",
      "fabrication_on_control": false
    },
    "method": "dual-blind dated-event ladder; KNOWN/UNKNOWN classification; fake-control measures fabrication tendency"
  },
  "latest_drift_check": {
    "status": "stable",
    "note": "matches the frozen empirical boundary",
    "frozen_cutoff_at_check": "2023-03-10",
    "method": "3-call drift ladder (anchor / first-post-cutoff / fake control)"
  },
  "drift_discipline": "Monthly 3-call drift alarm in .github/workflows/vintage-probe.yml (anchor forgotten / control fabricated / inconclusive -> red; post-cutoff learned -> green + amend note). A safe-drift result must be followed by an EXPLICIT contracts amendment, never a silent value change.",
  "leakage_note": "The pinned LLM never produces signal inside frozen OOS phases (all four claims are zero-LLM); the vintage gate exists for the E2/E3 causal-edge lanes where provider knowledge could leak into backtests."
}