{
  "after": "C286",
  "chosen_next_step": "C287: combine the17K and19K families into the complete four-node K structure at each supported annual index.",
  "reason": "The two successful target families share the same cumulative OFF intermediate, so their difference can reveal an additional source-qualified2K edge and a compact normal form.",
  "next_step_executed_within_this_step": false,
  "effort": "High sufficient",
  "limits": [
    "Co-located SP/LXX primary records remain different identities.",
    "All generated LXX records preserve native Cainan and the780 relation; no companion is copied.",
    "No global K law follows from a bounded endpoint classification."
  ]
}