curl --request POST \
  --url https://api.pocketenv.io/xrpc/io.pocketenv.variable.addVariable \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "variable": {
    "name": "<string>",
    "value": "<string>",
    "sandboxId": "<string>"
  }
}
'

{
  "error": "<string>",
  "message": "<string>"
}