Debug-Circular-Ref-Stringify-V2

The model receives the prompt (and optional system message). The run uses scorer rubric_json_metrics with the JSON configuration below. Pass/fail and partial credit are determined entirely by that scorer against the model output; no human grading.

Return JSON only with keys diagnosis, fix, tests. A logging utility calls JSON.stringify on a response object that contains a circular reference; the call throws a TypeError at runtime crashing the process. Identify the circular reference bug and fix it with a safe serialization approach.

{
  "metrics": {
    "repro": {
      "checks": [
        {
          "contains": [
            "circular"
          ]
        },
        {
          "contains": [
            "JSON.stringify"
          ]
        },
        {
          "contains": [
            "TypeError"
          ]
        },
        {
          "contains": [
            "reference"
          ]
        }
      ]
    },
    "hidden": {
      "checks": [
        {
          "contains": [
            "replacer"
          ]
        },
        {
          "contains": [
            "seen"
          ]
        },
        {
          "contains": [
            "WeakSet"
          ]
        }
      ]
    },
    "diagnose": {
      "checks": [
        {
          "contains": [
            "circular reference"
          ]
        },
        {
          "contains": [
            "serialization"
          ]
        },
        {
          "contains": [
            "JSON.stringify throws"
          ]
        }
      ]
    }
  }
}