Events guide
Notification callbacks
A mention does not send email. Hosted can POST comments.user_mentioned to an HTTPS endpoint you register on the dashboard. BYO returns events from your adapter. In both cases the payload is ids.
{
"event": "comments.user_mentioned",
"workspaceId": "ws_…",
"productId": "comments",
"timestamp": "2026-09-26T12:00:00.000Z",
"data": {
"eventId": "cme_…",
"schemaVersion": 1,
"appId": "cma_demo",
"environment": "test",
"tenantKey": "acme",
"resourceType": "task",
"resourceId": "task_1842",
"threadId": "thr_…",
"commentId": "cmt_…",
"actorId": "user_ada",
"mentionedUserId": "user_kai",
"occurredAt": "2026-09-26T12:00:00.000Z"
}
}Verify X-Bootstrapware-Signature (HMAC-SHA256 hex of the raw body, using the endpoint secret) on Hosted deliveries. Store eventId and skip duplicates. The POST may be retried once after 400 ms, and a failed delivery is not replayed forever. There is no body to quote in an email. If you email Kai, your server checks that Kai may read task_1842 in tenant acme, then loads the comment from your store or from an authorized Hosted read.
Self-mentions and replayed mutations do not emit a new mention event. Removing a mention emits nothing. Widget subscribe is a live refresh of ids for the open resource. It is not a notification inbox and it is not presence.
Signing and event names: webhooks.
Related: Mentions · Privacy by mode · Safe mentions