{
  "type": "object",
  "additionalProperties": false,
  "required": ["duplicate_of", "confidence", "evidence"],
  "properties": {
    "duplicate_of": {
      "type": ["integer", "null"],
      "description": "Issue number of the earlier report this duplicates, or null."
    },
    "confidence": {
      "type": "number",
      "minimum": 0,
      "maximum": 1
    },
    "evidence": {
      "type": "string",
      "description": "One sentence naming the shared root cause and symptom, or why nothing matched."
    }
  }
}