You're viewing the Kitchen Sink example - every writedocs feature combined in one site.
Request
curl -X POST "https://api.kitchen-sink.example.com/v1/widgets" \
  -H "Content-Type: application/json" \
  -H "X-API-Key: <X-API-Key>" \
  -d '{
  "name": "Sprocket",
  "color": "indigo"
}'
Response
{
  "name": "Sprocket",
  "color": "indigo",
  "id": "wdg_abc123"
}