import { createAdminClient } from '@spree/admin-sdk'

const client = createAdminClient({
  baseUrl: 'https://your-store.com',
  secretKey: 'sk_xxx',
})

const action = await client.promotions.actions.update('promo_UkLWZg9DAJ', 'pact_k5nR8xLqPz', {
  calculator: { type: 'percent_on_line_item', preferences: { percent: '15' } },
})

spree api patch /promotions/{promotion_id}/promotion_actions/{id} -d '{"calculator":{"type":"percent_on_line_item","preferences":{"percent":"15"}}}'

{
  "id": "pact_UkLWZg9DAJ",
  "created_at": "2026-01-15T12:00:00.000Z",
  "updated_at": "2026-01-15T12:00:00.000Z",
  "type": "create_item_adjustments",
  "promotion_id": "promo_UkLWZg9DAJ",
  "preferences": {},
  "calculator": {
    "type": "percent_on_line_item",
    "preferences": {
      "percent": "15.0",
      "apply_only_on_full_priced_items": false
    }
  },
  "line_items": null
}