> ## Documentation Index > Fetch the complete documentation index at: https://docs.isnap.ai/llms.txt > Use this file to discover all available pages before exploring further. # Event catalog > Describes the envelope every event shares, lists the 37 event types by family, and lists the changes that produce no event. Every event iSnap sends has the same envelope and one of 37 event types. This page describes the envelope, lists the types with the moment each one is sent, explains the two `metadata` fields every event carries, and lists the changes that no event announces. Read the last section before you build a copy of iSnap data from events alone. ## Envelope An event is a JSON object with six fields. The same object is the body of a delivery and an item of the [events feed](/webhooks/pulling-events). ```json theme={null} { "api_version": "v1", "event_id": "evt_Fh50GcqYY37ay4VjUxQ2rR6jN", "event_type": "message.received", "created_at": "2026-10-08T14:22:57.143Z", "trace_id": "174b4a27e4e4938fa67ea87b23a18579", "data": { "message": { "id": "msg_7Hq3Zd9Kp2Vx6Wn4Tb8Lc5Ym1", "line_id": "line_8Xk2mQ4vTn7Bw9Rz3Lc6Yp1Hd", "direction": "inbound", "kind": "message", "to": "+14155550124", "from": "+14155550123", "body": "Is the table still free at 8?", "channel": "iMessage", "service": "iMessage", "status": "delivered", "effect": null, "reply_to_message_id": null, "use_typing_indicator": true, "metadata": null, "attachments": [], "reactions": [], "scheduled_for": null, "schedule_reason": null, "reply_lane": false, "ignore_quiet_hours": false, "queue_info": null, "created_at": "2026-10-08T14:22:57.101Z", "queued_at": null, "sent_at": null, "delivered_at": "2026-10-08T14:22:56.000Z", "read_at": null, "failed_at": null, "error_code": null, "error_message": null, "cancelled_at": null }, "chat_id": "chat_6Rm1Yb5Tq9Hd3Kx7Wc2Ln8Vz4", "contact_name": "Dana Whitfield", "received_at": "2026-10-08T14:22:56.000Z", "metadata": null, "line_metadata": { "crm_account_id": "acct_4821" } } } ``` | Field | Type | Meaning | | - | - | - | | `api_version` | string | Always `v1`. It is not the version number of the API. | | `event_id` | string | `evt_` followed by 25 letters and digits. It identifies the event: every subscription, every attempt and every replay carries the same value. It is also the `webhook-id` header. | | `event_type` | string | One of the [event types](#event-types). | | `created_at` | string | When iSnap recorded the event, in ISO 8601 UTC with milliseconds. It is not when the change happened: that time is inside `data`. It is the same on every attempt and replay. | | `trace_id` | string | 32 hexadecimal characters, always present. Do not use it to match an event to a request: an event does not always carry the `trace_id` of the request that caused it. Match on the ids inside `data`, such as `data.message.id`. | | `data` | object | The fields of the event type, described on its [event page](#event-types). It always holds `metadata` and `line_metadata`. | Events carry personal data: message text, handles, contact names and attachment file names. Each event page lists the fields. Subscribe only to the event types you need. Do not copy personal data into logs, tickets or other tools, and refer to a contact by an id of your own. Read `event_id` and `event_type`: the envelope has no `id` and no `type` field. Ignore response fields, enum values and event types you do not know. Return `2xx` for an event type you do not handle. See [Versioning and compatibility](/api-reference/introduction#versioning-and-compatibility). ## Event types | Family | Event type | Sent when | | - | - | - | | `message` | [`message.queued`](/webhooks/events/message#message-queued) | A message is accepted for immediate sending, or a held message is released for sending. | | `message` | [`message.scheduled`](/webhooks/events/message#message-scheduled) | A message is accepted and held, or the planned send time of a held message moves by more than 15 minutes, except when it enters the reply lane. | | `message` | [`message.sent`](/webhooks/events/message#message-sent) | The line's device confirms it sent a message created through the API, or someone typed a message on the line's own device. | | `message` | [`message.delivered`](/webhooks/events/message#message-delivered) | The line's device reports for the first time that an outbound message was delivered. | | `message` | [`message.read`](/webhooks/events/message#message-read) | The recipient read a message you sent, or you marked a chat read. | | `message` | [`message.failed`](/webhooks/events/message#message-failed) | The line's device reports a failed send, or iSnap fails a message that was still waiting. | | `message` | [`message.received`](/webhooks/events/message#message-received) | An inbound message is stored. | | `message` | [`message.cancelled`](/webhooks/events/message#message-cancelled) | You cancel a queued or held message. | | `message` | [`message.fallback_triggered`](/webhooks/events/message#message-fallback_triggered) | The line's device reports that a message went out, or was attempted, over SMS or RCS instead of iMessage. | | `reaction` | [`reaction.added`](/webhooks/events/reaction#reaction-added) | The line's device confirms a reaction you added through the API. | | `reaction` | [`reaction.received`](/webhooks/events/reaction#reaction-received) | A contact adds a reaction to a message of the line. | | `reaction` | [`reaction.removed`](/webhooks/events/reaction#reaction-removed) | A reaction is removed, by the contact or by you. | | `typing_indicator` | [`typing_indicator.started`](/webhooks/events/typing-indicator#typing_indicator-started) | A contact starts typing in a chat with the line, on a line whose device detects typing. iMessage lines never send it. | | `typing_indicator` | [`typing_indicator.stopped`](/webhooks/events/typing-indicator#typing_indicator-stopped) | A contact stops typing in a chat with the line, on a line whose device detects typing. iMessage lines never send it. | | `line` | [`line.connected`](/webhooks/events/line#line-connected) | A BYOD device finishes pairing, a line that was announced offline or degraded recovers, or iSnap hands over a line whose device is connected. | | `line` | [`line.disconnected`](/webhooks/events/line#line-disconnected) | The line's device signs out, you terminate the line, a scheduled cancellation is carried out, the BYOD slots of the account no longer cover a BYOD line, or the hosted macOS session that the line runs on is released while a device session of the line runs on it. | | `line` | [`line.offline`](/webhooks/events/line#line-offline) | A BYOD line's device has not reported for 5 minutes, or the outage of another line reaches 15 minutes. | | `line` | [`line.degraded`](/webhooks/events/line#line-degraded) | A BYOD line can still send but no longer receives. | | `line` | [`line.apple_id_flagged`](/webhooks/events/line#line-apple_id_flagged) | The line's device reports that Apple disabled or restricted the line's Apple ID. | | `line` | [`line.quota_warning`](/webhooks/events/line#line-quota_warning) | A send brings one of the line's five sending limits to 80%. | | `line` | [`line.quota_exceeded`](/webhooks/events/line#line-quota_exceeded) | A send brings one of the line's five sending limits to 100%. | | `line` | [`line.capability_changed`](/webhooks/events/line#line-capability_changed) | One of four capabilities of a BYOD line moves between `active` and `degraded`. | | `line` | [`line.terminated`](/webhooks/events/line#line-terminated) | You terminate a line, a scheduled cancellation is carried out, or iSnap terminates a line. | | `line` | [`line.variant_changed`](/webhooks/events/line#line-variant_changed) | A rented line moves between inbound-only and two-way. | | `line` | [`line.variant_scheduled`](/webhooks/events/line#line-variant_scheduled) | A variant change is scheduled for a billing anchor of the line. | | `line` | [`line.variant_unscheduled`](/webhooks/events/line#line-variant_unscheduled) | You withdraw a scheduled variant change. | | `trial` | [`trial.linked`](/webhooks/events/trial#trial-linked) | A prospect pairs with a trial by sending its pairing code. | | `trial` | [`trial.dormant`](/webhooks/events/trial#trial-dormant) | The number of messages sent to the prospect without a reply reaches the trial's limit. | | `trial` | [`trial.reactivated`](/webhooks/events/trial#trial-reactivated) | A dormant trial becomes active again. | | `trial` | [`trial.bind_conflict`](/webhooks/events/trial#trial-bind_conflict) | A prospect sends a valid pairing code, but their handle is already paired with this pool line, or with as many pool lines of the pool as its limit allows. | | `trial` | [`trial.revoked`](/webhooks/events/trial#trial-revoked) | You revoke a trial that is `active`, `dormant`, or still inside its pairing window. | | `pre_order` | [`pre_order.fulfilled`](/webhooks/events/pre-order#pre_order-fulfilled) | The line of a pre-order is handed over. | | `pre_order` | [`pre_order.cancelled`](/webhooks/events/pre-order#pre_order-cancelled) | A pre-order ends before its build: you cancel it, its first month is not paid within 23 hours, or the payment of its first month is canceled before it is made. | | `macos_session` | [`macos_session.rented`](/webhooks/events/macos-session#macos_session-rented) | iSnap assigns a hosted macOS session to your account outside your own rent call. | | `macos_session` | [`macos_session.released`](/webhooks/events/macos-session#macos_session-released) | The rental of a hosted macOS session ends. | | `binding` | [`binding.released`](/webhooks/events/binding#binding-released) | A binding between a shared line and one contact ends. | | `webhook` | [`webhook.test`](/webhooks/events/webhook#webhook-test) | iSnap probes a suspended subscription. Never sent through an event filter. | Each "Sent when" cell is a summary. The event page states the exact cases, and the cases in which the event is not sent. ### Line events by line kind Not every line kind gets every `line.*` event. | Events | Sent for | | - | - | | `line.connected`, `line.offline` | BYOD lines: on every change. Rented lines and test lines: only for an outage that reaches 15 minutes and for the recovery from that outage, and `line.connected` when iSnap hands over a line whose device is connected. Shared lines: never. | | `line.degraded`, `line.capability_changed` | BYOD lines only. | | `line.apple_id_flagged` | Every line that has a device of its own. A shared line has none and never gets it. | | `line.disconnected`, `line.terminated` | Every line kind. On a shared line, `line.disconnected` carries `device_session_id: null`. | | `line.quota_warning`, `line.quota_exceeded` | Every line kind. Never for a trial. | | `line.variant_changed`, `line.variant_scheduled`, `line.variant_unscheduled` | Rented lines only. | A shared line has no device of its own. Besides the rows above, it never gets `message.sent` with `origin: "device"` or a `typing_indicator.*` event, and its inbound `message.received` is sent only for a contact the line has an active binding with. ## `metadata` and `line_metadata` Every event carries both fields in `data`, whatever its type. They hold the `metadata` you attached to resources, so that you can route an event without a second call. `data.metadata` is the `metadata` of the main resource of the event: | Family | `data.metadata` is the `metadata` of | | - | - | | `message.*` | The message. A message of a trial carries its own `metadata`, not the `metadata` of the trial. | | `reaction.*` | The message reacted to. | | `line.*` | The line. | | `trial.*` | The trial. | | `pre_order.*` | The pre-order. | | `macos_session.*` | The hosted macOS session. `macos_session.rented` always carries `null`: a rental starts without `metadata`. | | `typing_indicator.*`, `binding.*`, `webhook.*` | Nothing: always `null`. | It is `null` when that resource has no `metadata`, and when the resource is not yours. On a line that another account owned before you, an event about a message of that account carries `data.metadata: null`. A message event still carries the `metadata` of that message in `data.message.metadata`: see [Lines that change owner](/webhooks/overview#lines-that-change-owner). `data.line_metadata` is the `metadata` of the line the event is tied to, when that line belongs to your account. It is `null` otherwise: the event is tied to no line, the line has no `metadata`, or the event belongs to a trial that runs on a line you do not own. The `macos_session.*` events are the exception: they carry no line id and a line filter never matches them, and their `line_metadata` is the `metadata` of the line the session runs, or ran until the release, when that line is yours. On `line.*` events it equals `data.metadata`. Both fields are read once, when the event is recorded. Retries and replays carry the same values, even if the `metadata` changed since. Never put personal data or secrets in line `metadata`: it is readable by anyone who holds the line id, and it stays on a line that returns to the marketplace. See [Managing lines](/guides/managing-lines). ## What events do not announce The events announce the changes this catalog lists, and no other. Two rules apply before any list: * **An event is recorded only if it matches an active subscription when it occurs.** While a subscription is suspended or inactive, the events it would have matched are not recorded for it: they are not delivered later, cannot be replayed, and are absent from the events feed unless another active subscription of your account matched them. * **An event can be lost.** A change can stand without its event, which is then neither delivered nor listed in the events feed. Reconcile from the resource operations. Events also do not announce the following. **Webhook subscriptions** * A subscription that is suspended, resumed or turned inactive, including after a `410` response. * A signing secret that is rotated. * A subscription that is created, changed or deleted. **Lines: ownership and status** * A line that is reserved, activated, assigned or released, a reservation that expires, and a shared line that is created. * A line transferred to another account, for the earlier owner and for the next one. The device sessions a transfer ends produce no `line.disconnected`. * A line that leaves your account: the delivery statuses, read receipts and reactions that its device reports afterward about the messages you sent on it go to the account that owns the line at that time, or to no account when the line has no owner. Each message event carries the message it concerns, with its text, its handles, its attachment file names and its `metadata`; a reaction event carries the id of that message and the handle of the contact. You do not receive them. A mark-read by the next owner also marks read the inbound messages you had not marked read, and sends their content to that owner in `message.read`. Never put secrets in message `metadata`, and refer to a contact there by an id of your own. See [Lines that change owner](/webhooks/overview#lines-that-change-owner). * A line that iSnap suspends, and the end of that suspension. The device sessions a suspension ends produce no `line.disconnected`. * A rented line that returns to the marketplace because its per-line subscription ended: no `line.terminated` and no other event. * A BYOD line ended because the BYOD slots of the account no longer cover it: `line.disconnected` is sent, `line.terminated` is not. * A line that iSnap terminates: `line.terminated` is sent, `line.disconnected` is not. * A cancellation that is scheduled or withdrawn (`POST /v1/lines/{id}/cancel`, `POST /v1/lines/{id}/uncancel`). The events come when the cancellation is carried out. * An anniversary that is set, and a conversion to or from a test line. * A scheduled variant change that is dropped, when the line is released, transferred or turned into a test line, or at the billing anchor when the line is suspended or already has that variant: no `line.variant_unscheduled`. **Lines: settings, health and number** * A change of a line's configuration (`PATCH /v1/lines/{id}/config`) or `metadata` (`PATCH /v1/lines/{id}`). * A device session that is replaced by a new pairing on the same line, or revoked by iSnap. `line.disconnected` covers only the cases its section lists. * For a rented, shared or test line: an outage shorter than 15 minutes and its end, a line that stops receiving or recovers, and a capability change. * For a BYOD line: a capability that moves to or from `disabled`, and a change of a capability other than `imessage`, `sms_fallback`, `send_text` and `send_attachment`. * An Apple ID flag that is cleared. A device report that repeats an existing flag sends nothing either. * A sending-limit counter that falls back below a threshold or resets. * A phone number that changes or is corrected, and the number of a BYOD line when its device first reports it. **Messages, reactions and typing** * A delivery status, a read receipt or a reaction that concerns a message that iSnap has deleted at the end of its retention. * A status the message already has, a second copy of an inbound message, and history that a device reports from before iSnap was watching the line. * A message typed on the device of a shared line or of a line that runs trials: no `message.sent`. * An inbound message that iSnap does not record: on a shared line, a message from a contact the line has no active binding with; on a line that runs trials, a message from a sender who is not paired. * A message deleted at the end of its retention. An edited or unsent message is not reported at all. * A canceled message of a trial: no `message.cancelled`. * A typing indicator you start or stop. * A reaction that the line's device fails to place, and a reaction or a removal that never reaches a device. **Trials** * A trial that is created or updated, and a pairing window that expires. * A text that matches no pairing code, and the confirmation and limit notices iSnap sends to the prospect. **Pre-orders** * A pre-order that is created or confirmed, and a first month that is paid. * An order that iSnap cancels behind a pre-order whose build has started. * An estimated fulfillment time that passes. **Hosted macOS sessions** * Your own rent, update, cancel and uncancel calls. **Other resources** * A binding that is created: the first `message.queued` or `message.scheduled` to a new contact is the signal. * Chats, attachments (including an attachment that becomes `ready`, `failed` or `expired`), recipient lookups and their results, API keys, billing and invoices: no event family exists for them. ### How to reconcile Treat events as a signal to act fast, and the resource operations as the source of truth. Read the state again on a schedule, and after any period in which your endpoint was down or your subscription was suspended or inactive. | To know | Read | | - | - | | The messages iSnap keeps, and their statuses | [`GET /v1/messages`](/api-reference/messages/list-messages), or [`GET /v1/messages/{id}`](/api-reference/messages/get-message) for one message | | Your lines and their status | [`GET /v1/lines/my`](/api-reference/lines/list-my-lines) lists your lines that are `active` or `reserved`. [`GET /v1/lines/{id}`](/api-reference/lines/get-line) returns one rented or BYOD line in any status. | | The lines that have a fault now | [`GET /v1/attention`](/api-reference/lines/list-attention) | | The health of a BYOD line, its Apple ID flag included | [`GET /v1/lines/{id}/health`](/api-reference/lines/get-line-health) | | A trial | [`GET /v1/trial/{trial_id}`](/api-reference/trials/get-trial) | | A pre-order | [`GET /v1/pre-orders/{id}`](/api-reference/pre-orders/get-pre-order) | | A hosted macOS session | [`GET /v1/macos-sessions/{id}`](/api-reference/macos-sessions/get-macos-session) | | Your subscriptions and their failures | [`GET /v1/webhooks`](/api-reference/webhooks/list-webhooks) and [`GET /v1/webhooks/{id}/deliveries`](/api-reference/webhooks/list-webhook-deliveries) | | The events of the last 72 hours that matched a subscription of your account | [`GET /v1/webhooks/events`](/api-reference/webhooks/list-webhook-events): see [Events feed](/webhooks/pulling-events) | This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.