Changelog and lifecycle

Version lifecycle

Dated version	Status	Notes
`2026-10-01`	Draft	Private beta: read, sync, availability, and narrowly scoped writes.

The first beta version is not frozen. A support and deprecation window will be published before general availability; none is promised yet.

Added OAuth apps and app events.
Added key expiry, key rolling, and the 49-character key format with a checksum.
Webhook secret rotation can overlap; during the overlap the signature header carries one v1 per secret.
Added delivery-log error classes, plan pauses (plan_paused), and per-address rate limits (ip_rate_limited).
Added the Talki-Version header to every operation, and unsupported_version.

Added appointment, contact, and service retrieve endpoints and commit-ordered change feeds.
Added resumable call recovery through GET /v1/calls?sync=true; timestamp filters remain available for reporting windows.
Added GET /v1/availability for timed and day-range services.
Added appointment create, reschedule, and cancel operations with required idempotency keys and stable booking-conflict codes.
Added contact upsert with trusted-name provenance and external references.
Added the narrow service update operation.
Added the resource change feed and retrieve endpoint, with resources:read, and a two-field resource update behind resources:write.
Added the unresolved-request change feed and retrieve endpoint, with unresolved:read.
Removed the unused webhooks:manage scope.
origin on webhook events now carries the API credential and idempotency key of a write, so a consumer can recognise its own changes.
Delivery headers are X-Talki-*, and the user agent is Talki-Webhooks/1.0.
Removed the legacy flat fields from call.ended and appointment.created; resource payloads now use data.object only.

Published GET /v1/account, GET /v1/calls, and GET /v1/calls/{call_id}.
Added scoped API-key authentication, public request IDs, stable error envelopes, and per-credential rate limits.
Added canonical objects to call, appointment, and contact webhook events.
Added account_id and origin to the webhook envelope.