Cost-Short-Fix-Sum-Of-N

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 benchmark, title, patch, done. Set benchmark to "cost", title to "Fix off-by-one in sum of first n integers", and done to true. A loop sums i < n instead of including n. Provide a concise fix.

{
  "metrics": {
    "strict": {
      "checks": [
        {
          "contains": [
            "cost"
          ]
        },
        {
          "contains": [
            "done"
          ]
        },
        {
          "contains": [
            "include n"
          ]
        },
        {
          "contains": [
            "<="
          ]
        },
        {
          "contains": [
            "sum"
          ]
        }
      ]
    }
  }
}