Envelope

One event on the local bus.

Type object

Shape

Field	Type	Description
event_idrequired	EventId
namerequired	EventName	A registry-validated dotted event name, e.g. `document.created`. Construct literals through [`crate::event_name!`], which fails the build on a name missing from the registry; a runtime-built name is refused by [`crate::validate`] at the boundary instead.
versionrequired	integer (uint16, >= 0, <= 65535)	The `(name, version)` pair identifies the payload shape. Bumped per event name on breaking change only; additive attrs do not bump it, and a pair is never reused with a different meaning.
occurred_at_msrequired	integer (int64)	Wall clock, epoch ms UTC. Display and bucketing ONLY - never ordering.
actorrequired	Actor	Who caused an event.
originrequired	Origin	Where the event was minted.
scope	Scope	Where in the data model the event applies. The profile is usually implicit (the journal is profile-local today); it is carried so a multi-profile device can tell its own events apart.
subject	Subject or null
correlation_id	EventId or null	The chain root. `None` means this event is its own root - readers use [`Envelope::chain_root`], never the raw field.
causation_id	EventId or null	The immediate parent event.
attrs	map of string to AttrValue

Example

{
  "event_id": "00000000-0000-4000-8000-000000000000",
  "name": "string",
  "version": 0,
  "occurred_at_ms": 0,
  "actor": {
    "kind": "user",
    "id": "00000000-0000-4000-8000-000000000000",
    "token": "string"
  },
  "origin": {
    "device_id": "00000000-0000-4000-8000-000000000000",
    "session_id": {}
  },
  "scope": {
    "profile_id": "00000000-0000-4000-8000-000000000000",
    "workspace_id": "00000000-0000-4000-8000-000000000000"
  },
  "subject": {
    "kind": "workspace",
    "id": "string",
    "version": 0
  },
  "correlation_id": "00000000-0000-4000-8000-000000000000",
  "causation_id": "00000000-0000-4000-8000-000000000000",
  "attrs": {
    "key": {
      "t": "id",
      "v": "00000000-0000-4000-8000-000000000000"
    }
  }
}

The contract has no example values, so example bodies are generated from each schema: every field is shown with a placeholder of its type.

Generated from contract version 1. Last updated November 12, 2026.