curl -X POST "https://api.joinformal.com/core.v1.UserService/ListUserExternalIds" \
  -H "X-API-KEY: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "example": "value"
  }'

{
  "externalIds": [
    {
      "id": "<string>",
      "externalId": "<string>",
      "userId": "<string>",
      "appId": "<string>",
      "description": "<string>",
      "createdAt": "2023-11-07T05:31:56Z",
      "updatedAt": "2023-11-07T05:31:56Z"
    }
  ],
  "listMetadata": {
    "after": "<string>",
    "before": "<string>",
    "count": 123,
    "nextCursor": "<string>"
  }
}