curl --request POST \
  --url https://api.iotools.cloud/v1/tool/tolerance-stackup-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "units": "mm",
  "dimensions": "Bore diameter, +, 25.400, 0.050\nShaft diameter, -, 25.350, 0.030\nRetaining ring width, -, 0.020, 0.005"
}
'

{
  "tool": "tolerance-stackup-calculator",
  "tool_version": "1.0.1",
  "outputs": {
    "summary": [
      {
        "metric": "Nominal Stack",
        "value": "0.030 mm"
      },
      {
        "metric": "Contributors",
        "value": "3"
      },
      {
        "metric": "Worst-Case Tolerance",
        "value": "±0.085 mm"
      },
      {
        "metric": "Worst-Case Range",
        "value": "-0.055 to 0.115 mm"
      },
      {
        "metric": "Statistical (RSS) Tolerance",
        "value": "±0.059 mm"
      },
      {
        "metric": "Statistical (RSS) Range",
        "value": "-0.029 to 0.089 mm"
      },
      {
        "metric": "RSS vs. Worst-Case",
        "value": "31.1% tighter"
      }
    ],
    "contributors": [
      {
        "dimension": "Bore diameter",
        "dir": "+",
        "nominal": "25.400 mm",
        "tolerance": "±0.050 mm",
        "worst-case-share": "58.8%",
        "rss-variance-share": "73.0%"
      },
      {
        "dimension": "Shaft diameter",
        "dir": "-",
        "nominal": "25.350 mm",
        "tolerance": "±0.030 mm",
        "worst-case-share": "35.3%",
        "rss-variance-share": "26.3%"
      },
      {
        "dimension": "Retaining ring width",
        "dir": "-",
        "nominal": "0.020 mm",
        "tolerance": "±0.005 mm",
        "worst-case-share": "5.9%",
        "rss-variance-share": "0.7%"
      }
    ]
  },
  "credits_used": 3,
  "credits_remaining": null
}