{
  "webhook": "my-cost-report",
  "before": [
    {
      "url": "http://localhost:8800/usage-clear",
      "body": {}
    },
    {
      "url": "http://localhost:8800/budget/reset",
      "body": {}
    },
    {
      "url": "http://localhost:8800/usage",
      "body": {
        "items": [
          {
            "request_id": "r1",
            "user": "이준호",
            "step": "answer",
            "model": "gpt-4.1-mini",
            "prompt_tokens": 1000,
            "completion_tokens": 100,
            "cost_usd": 0.00056,
            "route": "자동 답변"
          },
          {
            "request_id": "r1",
            "user": "이준호",
            "step": "classify",
            "model": "gpt-5.4-nano",
            "prompt_tokens": 100,
            "completion_tokens": 20,
            "cost_usd": 4.5e-05,
            "route": "자동 답변"
          },
          {
            "request_id": "r2",
            "user": "박서연",
            "step": "answer",
            "model": "gpt-4.1-mini",
            "prompt_tokens": 2000,
            "completion_tokens": 200,
            "cost_usd": 0.00112,
            "route": "자동 답변"
          },
          {
            "request_id": "r3",
            "user": "이준호",
            "step": "answer",
            "model": "gpt-4.1-mini",
            "prompt_tokens": 500,
            "completion_tokens": 40,
            "cost_usd": 0.000264,
            "route": "자동 답변"
          }
        ]
      }
    }
  ],
  "after": [
    {
      "url": "http://localhost:8800/budget/reset",
      "body": {}
    },
    {
      "url": "http://localhost:8800/usage-clear",
      "body": {}
    }
  ],
  "cases": [
    {
      "name": "모두 nano였다면",
      "body": {
        "requests_per_day": 100,
        "workdays": 22,
        "what_if_model": "gpt-5.4-nano"
      },
      "expect": {
        "equals": {
          "what_if.model": "gpt-5.4-nano",
          "what_if.cost_usd": 0.00117,
          "what_if.saving_usd": 0.000819,
          "what_if.projected_month_usd": 0.858
        }
      }
    },
    {
      "name": "원래 숫자는 그대로",
      "body": {
        "requests_per_day": 100,
        "workdays": 22,
        "what_if_model": "gpt-5.4-nano"
      },
      "expect": {
        "equals": {
          "cost_usd": 0.001989,
          "projected_month_usd": 1.4586
        }
      }
    },
    {
      "name": "모두 mini였다면 · 아끼는 돈이 음수",
      "body": {
        "what_if_model": "gpt-4.1-mini"
      },
      "expect": {
        "equals": {
          "what_if.cost_usd": 0.002016,
          "what_if.saving_usd": -2.7e-05
        }
      }
    },
    {
      "name": "없는 모델은 400",
      "body": {
        "what_if_model": "gpt-9"
      },
      "expect": {
        "status": 400,
        "equals": {
          "error": "unknown model"
        },
        "contains": {
          "known": [
            "gpt-5.4-nano"
          ]
        }
      }
    },
    {
      "name": "what_if 없이 부르면 과제 1과 같음",
      "body": {},
      "expect": {
        "equals": {
          "what_if": null,
          "requests": 3
        }
      }
    }
  ]
}