generated: '2026-07-17'
method: searched
source: >-
  https://help.activityhero.com/api and the linked Registration API / Schedule
  API help-center articles. ActivityHero publishes no OpenAPI, so these
  cross-cutting semantics are transcribed from the provider docs.
description: >-
  Cross-cutting semantics of ActivityHero's provider integration surface. The
  surface is webhook-based rather than a request/response REST API, so several
  conventional REST concerns (pagination, idempotency keys, sparse fields) do
  not apply. What is documented: JSON payloads, HMAC-SHA256 message signing, an
  action-typed event envelope, and a per-call batch ceiling.
provider: ActivityHero
docs: https://help.activityhero.com/api
api_style: Outbound webhooks (HTTPS POST, JSON payloads); no inbound REST base URL published.
authentication:
  scheme: HMAC-SHA256 signature over "providerID_timestamp" in a Signature header
  detail: authentication/activityhero-authentication.yml
  docs: https://help.activityhero.com/can-i-sync-activityhero-registrations-to-my-own-database
event_envelope:
  action_field: action
  action_values: [enrolled, update, cancelled]
  identity_fields: [provider_id, timestamp]
  payload_field: data (array of objects)
  detail: asyncapi/activityhero-webhooks.yml
serialization:
  content_type: application/json
  accept: application/json
idempotency:
  supported: false
  note: No idempotency-key mechanism is documented; delivery is a signed POST per event.
pagination:
  supported: false
  note: Not applicable to the webhook surface.
batching:
  schedule_sync_max_sessions_per_call: 100
  over_limit_behavior: Returns an error; use manual CSV import for larger batches.
versioning:
  documented: false
  note: No API version header or dated version scheme is published.
rate_limit_signaling:
  documented: false
zapier:
  supported: true
  article: https://help.activityhero.com/how-do-i-use-the-activityhero-registration-api-with-zapier