{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/galileo-ai/main/json-schema/galileo-ai-metric-schema.json",
  "title": "Galileo Metric",
  "description": "A metric value produced by a Galileo evaluator (built-in, Luna, or custom) against a span, trace, or dataset row.",
  "type": "object",
  "required": ["name", "value"],
  "properties": {
    "name": { "type": "string" },
    "type": {
      "type": "string",
      "enum": ["builtin", "luna", "custom"]
    },
    "value": {
      "oneOf": [
        { "type": "number" },
        { "type": "boolean" },
        { "type": "string" }
      ]
    },
    "explanation": {
      "type": "string",
      "description": "Optional natural-language rationale produced by the evaluator."
    },
    "judge_model": {
      "type": "string",
      "description": "Identifier of the judge model used (LLM-as-judge or Luna)."
    }
  },
  "additionalProperties": true
}