{
  "cause": "Unconstrained Cartesian IK crossed the knee straightening singularity into the reverse-flexion branch; AMP reproduced that invalid expert.",
  "policy_phase_aligned_to_source": false,
  "official_bridge_artifact": false,
  "fixed_reference_dynamically_validated": false,
  "urdf_modified": false,
  "run_rejected": "/home/z/bridge/rl/bridge_amp_v4/logs/2026-10-20_14-19-43_t800_v4_straight_fresh_4096",
  "measurements": {
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  "preflight_rejects_old_expert": true
}