{
  "$schema": "https://json-structure.org/draft-00/schema",
  "name": "FixerFluctuationResponse",
  "description": "JSON Structure for a Fixer fluctuation envelope (rate change summary per currency).",
  "type": "object",
  "properties": {
    "success": { "type": "boolean" },
    "fluctuation": { "type": "boolean" },
    "start_date": { "type": "string", "x-format": "date" },
    "end_date": { "type": "string", "x-format": "date" },
    "base": { "type": "string", "x-format": "iso4217" },
    "rates": {
      "type": "map",
      "values": {
        "type": "object",
        "properties": {
          "start_rate": { "type": "double" },
          "end_rate": { "type": "double" },
          "change": { "type": "double" },
          "change_pct": { "type": "double" }
        },
        "required": ["start_rate", "end_rate", "change", "change_pct"]
      }
    }
  },
  "required": ["success", "fluctuation", "start_date", "end_date", "base", "rates"]
}