Aevum Event Schema v1¶

The machine-readable JSON Schema is at spec/aevum-event-v1.json.

The schema defines the structure of every AuditEvent produced by the episodic ledger. See the Signing Specification for verification procedures.

Field summary¶

See the JSON Schema for full constraints. Key fields:

Field	Type	Description
event_id	string	UUID v7 (globally unique, time-ordered)
episode_id	string	Groups events into a logical workflow episode
sequence	integer	Chain position (1-based); always 1 for session.start
event_type	string	Dotted namespace (e.g. `session.start`, `ingest.accepted`)
actor	string	Who caused this event (e.g. `aevum-core`, `agent`)
system_time	integer	HLC nanoseconds — use for causal ordering
valid_from	string	Wall-clock ISO 8601 timestamp
valid_to	string\|null	Validity end timestamp; null for point-in-time events
causation_id	string\|null	audit_id of the causing event
correlation_id	string\|null	Deployment-wide correlation token
trace_id	string\|null	OTel W3C trace ID
span_id	string\|null	OTel W3C span ID
prior_hash	string	SHA3-256 of previous event's signing fields
payload_hash	string	SHA3-256 of payload (JCS-canonical)
signature	string	Ed25519 over SHA3-256(signing fields), base64url
signer_key_id	string	Signing key identifier
schema_version	string	Always `"1.0"`
payload	object	Event-specific structured data
audit_id	string	`urn:aevum:audit:{event_id}`

event_type	Description
`session.start`	Kernel startup; always sequence 1
`ingest.accepted`	Data ingested through the governed membrane
`ingest.rejected`	Ingest denied by policy or consent
`query.accepted`	Graph traversal executed
`review.created`	Review checkpoint created
`commit.accepted`	Manual commit appended
`replay.started`	Replay of a past decision begun
`capture.gap`	Out-of-band capture surface call declared

{
  "capture_surface": {
    "llm": false,
    "mcp": false
  },
  "key_provenance": "in-process"
}

key_provenance values: in-process, external, vault-transit, aws-kms, pkcs11.

{
  "gap_type": "llm",
  "reason": "direct_api_call",
  "model_hint": "claude-opus-4-7"
}

gap_type values: llm, mcp, tool, custom. reason and gap_type are required; model_hint is optional.