{
  "after": "C281",
  "chosen_next_step": "C282: test the tagged mixed-Cainan1058=598+460=2K route and whether its retained endpoint completes a15K+2K=17K path.",
  "reason": "The successful460 state comparison now allows the two Cainan modes to be compared explicitly while retaining their distinct labels; this addresses the central529 observation.",
  "next_step_executed_within_this_step": false,
  "effort": "High sufficient",
  "limits": [
    "No MT companion rail is admitted.",
    "Missing source records cannot be supplied by covariance alone.",
    "Regular Cainan remains130, cumulative Cainan460."
  ]
}