curl --request POST \
  --url https://api.iotools.cloud/v1/tool/earthing-conductor-sizing-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "faultCurrent": "10",
  "clearingTime": "0.5",
  "materialPreset": "copper-pvc",
  "minSize": "0"
}
'

{
  "tool": "earthing-conductor-sizing-calculator",
  "tool_version": "1.0.2",
  "outputs": {
    "requiredArea": "49.45 mm²",
    "recommendedSize": "50 mm² (next standard size ≥ 49.45 mm²)",
    "breakdownTable": [
      {
        "item": "Fault current (I)",
        "value": "10.000 kA (10,000 A)"
      },
      {
        "item": "Disconnection time (t)",
        "value": "0.500 s"
      },
      {
        "item": "Material / insulation",
        "value": "Copper, PVC insulated (70°C)"
      },
      {
        "item": "k constant",
        "value": "143"
      },
      {
        "item": "Calculated theoretical area (S = I×√t / k)",
        "value": "49.45 mm²"
      },
      {
        "item": "Recommended standard size",
        "value": "50 mm²"
      },
      {
        "item": "Margin over theoretical minimum",
        "value": "+0.55 mm² (1.1%)"
      }
    ]
  },
  "credits_used": 5,
  "credits_remaining": null
}