curl --request GET \
  --url https://studio.edgeimpulse.com/v1/api/{projectId}/raw-data/metadata \
  --header 'x-api-key: <api-key>'

{
  "success": true,
  "metadata": [
    {
      "id": 123,
      "metadata": {}
    }
  ],
  "error": "<string>"
}