curl --request POST \
  --url https://api.iotools.cloud/v1/tool/stair-rise-run-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "totalRise": "108",
  "unit": "in",
  "solveMode": "riser",
  "targetRiser": "7",
  "stepCount": "14"
}
'

{
  "tool": "stair-rise-run-calculator",
  "tool_version": "1.0.1",
  "outputs": {
    "results": [
      {
        "metric": "Number of steps (risers)",
        "value": "15"
      },
      {
        "metric": "Number of treads",
        "value": "14"
      },
      {
        "metric": "Riser height (each)",
        "value": "7.20 in"
      },
      {
        "metric": "Tread depth (each)",
        "value": "10.60 in"
      },
      {
        "metric": "Total run",
        "value": "148.40 in"
      },
      {
        "metric": "Stair angle",
        "value": "34.2°"
      },
      {
        "metric": "Comfort rule (2R + T)",
        "value": "25.00 in"
      },
      {
        "metric": "Code compliance",
        "value": "Within common comfort range (7.00 in-7.75 in riser, 10.00 in-11.00 in tread)"
      }
    ],
    "summary": "15 risers × 7.20 in · 14 treads × 10.60 in · run 148.40 in · 34.2°"
  },
  "credits_used": 3,
  "credits_remaining": null
}