{
  "topic_id": "TP-026",
  "synthetic": true,
  "real_customer_data": false,
  "purpose": "Purchase net of merchant refunds differs from debt movement",
  "input": {
    "currency": "USD",
    "opening_debt": 300,
    "rows": [
      {
        "type": "Purchase",
        "amount": 120
      },
      {
        "type": "Refund",
        "amount": -20
      },
      {
        "type": "Repayment",
        "amount": -200
      },
      {
        "type": "Interest",
        "amount": 5
      }
    ]
  },
  "expected_review": {
    "net_purchases": 100,
    "signed_movement": -95,
    "closing_debt": 205
  },
  "scope": "Types are explicitly established for this exercise, not inferred by extraction or SUMIFS. Excel not executed.",
  "verification": "Python reference model only. Vendor UI, accounting operations, real bank compatibility and authenticated imports NOT_VERIFIED."
}