{
  "observed_date": "2026-09-14",
  "baseline_engine": "d4e7cdd5b53e97666afb40c512223def0401539c",
  "candidate_engine": "59a0c95aaec9c14ddd7384bb451d6d90eb3abec7",
  "scope": "isolated core regression; not Source or broker acceptance",
  "reproduced": [
    {
      "test": "successor_without_frozen_instrument_metadata_is_not_an_implicit_new_security",
      "before": "returned success and created 300 shares of an instrument absent from the frozen metadata",
      "after": "successor_instrument_missing, original ledger and notes unchanged"
    },
    {
      "test": "invalid_successor_terms_cannot_be_replaced_with_one_share_or_zero_cash",
      "before": "missing ratio accepted as 1.0",
      "after": "all 13 malformed term cases rejected without mutation"
    },
    {
      "test": "a_late_corporate_batch_failure_keeps_prior_cash_positions_and_notes",
      "before": "an overflowing cash leg failed after deleting the old position and retaining a successor plus a cash receivable",
      "after": "whole batch rejected, including original target quantity and weight state, notes unchanged"
    }
  ],
  "local_tests": {
    "core": {
      "passed": 907,
      "ignored": 9
    },
    "trading": {
      "passed": 625,
      "ignored": 63
    },
    "runner": {
      "passed": 463,
      "ignored": 9
    },
    "api": {
      "passed": 129,
      "ignored": 7
    }
  },
  "completed_engine_replay_cases": 12,
  "engine_replay_cases": "paper/gt/qmt observation origins x timely/late x buy/sell; each paired with complete/missing successor metadata",
  "live_order_or_cancel_requests": 0,
  "source_runtime_modified": false,
  "ui_modified": false
}