generated: '2026-10-07'
method: searched
source: https://saperly.com/docs/guides/webhooks
description: Saperly pushes events to a per-number HTTPS webhook (POST /numbers/{id}/webhook, operationId numbers.setWebhook)
  or a workspace default set in the dashboard. Delivery is inline-first, then queued with retries and a dead-letter
  queue. Every delivery is HMAC-SHA256 signed.
configure:
  operationId: numbers.setWebhook
  path: POST /numbers/{id}/webhook
  body:
    url: https://…
  workspace_default: dashboard Settings → Webhooks (delivery inspection, stats, test sends)
envelope:
  deliveryId: UUID v4
  eventType: string
  payload: object
events:
- name: call.received
  when: An inbound call reached one of your numbers
  payload:
  - callId
  - connectionId
  - from
  - to
- name: call.completed
  when: A call connected and then ended
  payload:
  - callId
  - 'status: "completed"'
  - durationSec
  - costCents
  - from
  - to
  - hangupCause?
- name: call.failed
  when: A call never connected — the callee did not answer, the carrier could not place it, or it was declined before
    answer
  payload:
  - callId
  - 'status: "no_answer" | "failed"'
  - 'durationSec: 0'
  - 'costCents: 0'
  - from
  - to
  - hangupCause?
- name: call.recording.saved
  when: A call's recording is ready to fetch
  payload:
  - callId
  - …
- name: message.received
  when: An inbound SMS reached one of your numbers
  payload:
  - messageId
  - numberId
  - to
  - from
  - body
also_documented: 10DLC status updates and delivery receipts arrive via webhook (named in prose on the webhooks and
  compliance guides; payloads not tabulated)
signature:
  algorithm: HMAC-SHA256
  header: x-saperly-signature
  format: v1=<hex>
  signed_payload: '`${timestamp}.${rawBody}`'
  timestamp_header: x-saperly-timestamp
  delivery_id_header: x-saperly-delivery-id
  verification: recompute over the raw bytes, constant-time compare, reject stale timestamps, dedup on x-saperly-delivery-id
    for at least 5 minutes
  sdk: '@trysaperly/sdk verifyWebhook(rawBody, secret, headers); the Python SDK ships webhook verification'
delivery:
  first_attempt: inline (synchronous)
  retries: queued and retried on non-2xx or timeout
  dead_letter: deliveries that exhaust their retries land in a dead-letter queue
  acknowledge: return a 2xx quickly
  terminal_guarantee: exactly one terminal event (call.completed or call.failed) per call; a call refused before
    attempt (insufficient balance) produces no event
asyncapi: null
asyncapi_note: No AsyncAPI document is published; the provider's webhook catalog is captured here from the docs.