curl --request POST \
  --url https://api.interchange.io/api/v2/buyer/campaigns/{campaignId}/creative-sessions/{sessionId}/evaluate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "stage": "draft",
  "selected_variant_id": "<string>"
}
'

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}