Idempotency-Key on send-to-device and POST /api/public/subscriptions, in the sandbox

Idempotency-Key on send-to-device and POST /api/public/subscriptions, in the sandboxPOST /api/public/orders/{orderId}/send-to-device and POST /api/public/subscriptions accept an optional Idempotency-Key header, the same way the refund and the cancellation do: 1 to 255 printable ASCII characters, a new value for every send or subscription request and the same value when you retry…This page needs JavaScript. The same content is available as Markdown: /changelog/2026-11-02-api-public-idempotency-send-to-device-subscriptions.md. Every document for agents is listed in /llms.txt.