Webhooks reference

Complete reference for Lattica webhook events. For setup and signature verification, see Zapier and webhooks.

Common payload structure

Every webhook delivery has the same envelope:

{
  "event": "task.created",
  "delivered_at": "2026-04-12T10:14:22Z",
  "workspace_id": "ws_8FjK4q",
  "actor": {
    "type": "user",
    "id": "usr_a91kp2",
    "name": "Priya Shah"
  },
  "data": { ... event-specific payload ... }
}

Headers

Header	Description
`X-Lattica-Event`	Event name, e.g. `task.created`
`X-Lattica-Signature`	HMAC-SHA256 of body, prefixed `sha256=`
`X-Lattica-Delivery-Id`	Unique ID per delivery — log it, dedupe with it
`X-Lattica-Workspace`	Workspace ID
`X-Lattica-Webhook-Id`	The configured webhook endpoint’s ID

Task events

task.created — new task
task.updated — any field changed; payload includes changes object
task.deleted — soft-deleted (still recoverable for 30 days)
task.completed — moved into a status configured as terminal
task.reopened — moved back out of a terminal status
task.assigned — assignee set or changed
task.unassigned — assignee cleared
task.due_soon — fires 24h before due date
task.overdue — fires once when due date passes

Project events

project.created
project.updated
project.archived
project.member_added
project.member_removed

Comment events

comment.created
comment.updated
comment.deleted

Workspace events

member.invited
member.joined
member.removed
member.role_changed
billing.plan_changed
billing.payment_failed

Sample: task.updated

{
  "event": "task.updated",
  "delivered_at": "2026-04-12T10:14:22Z",
  "workspace_id": "ws_8FjK4q",
  "actor": { "type": "user", "id": "usr_a91kp2", "name": "Priya Shah" },
  "data": {
    "task": {
      "id": "task_d3Bk2e",
      "title": "Customer onboarding call — Acme",
      "status": "in_progress",
      "assignee_id": "usr_a91kp2",
      "due_date": "2026-04-15"
    },
    "changes": {
      "status": { "from": "todo", "to": "in_progress" }
    }
  }
}

Idempotency

Webhook deliveries are at-least-once. Use X-Lattica-Delivery-Id to dedupe on your side — store the ID after successful processing and reject duplicates.