curl --request POST \
  --url https://api.open.cx/workflows/validate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "trigger_type": "manual-trigger",
  "workflow_blocks": [
    "<unknown>"
  ]
}
'

{
  "valid": true,
  "issues": [
    {
      "step_id": "<string>",
      "message": "<string>"
    }
  ],
  "action_types_used": [
    "<string>"
  ]
}