# core/events — AGENTS.md

## Purpose

Foundational event-sourcing infrastructure: all `EventPayload` definitions for every domain, the serialization registry, the `EventStore` interface, the `EventReplayer` contract, and shared identity/vocabulary types used across the entire `core/` layer.

## Ownership

CORREX kernel team. This is the most cross-cutting module in the codebase — changes here can break every other module. Coordinate before adding or renaming event types.

## Local Contracts

- `EventPayload` — sealed interface that every domain event implements.
- `StoredEvent` / `EventEnvelope` / `EventMetadata` — envelope types wrapping payloads for storage and replay.
- `EventStore` — interface for appending and querying events. Implementations in `infrastructure/`.
- `EventReplayer<S>` / `DefaultEventReplayer<S>` — replays a filtered event stream through a `Projection<S>` to rebuild state.
- `Projection<S>` — interface: `initial(): S` + `apply(state, event): S`.
- `StateBuilder` / `DefaultStateBuilder` — convenience builder over `EventReplayer`.
- `Serialization.kt` — the `eventModule` polymorphic block. **Every new `EventPayload` subclass must be registered here.** Missing registration = silent deserialization failure.
- `JsonEventSerializer` / `EventSerializer` — serialize/deserialize `StoredEvent` to JSON.
- `EventDispatcher` — broadcasts events to in-process listeners.
- Domain event files: `ApprovalEvents`, `ArtifactEvents`, `ContextEvents`, `InferenceEvents`, `OrchestrationEvents`, `RouterEvents`, `SessionEvents`, `TaskEvents`, `ToolEvents`, `IntentEvents`, `RiskAssessedEvent`, `JournalCompactedEvent`, and many more — all payload definitions live here.
- `LspDiagnosticsCompletedEvent` records pulled language-server diagnostics or a graceful skip reason; replay consumes this observation and never contacts the server.
- Shared vocabulary: `IdentityTypes` (SessionId, TaskId, etc.), `Tier`, `TokenUsage`, `ToolReceipt`, `ToolRequest`, `RiskLevel`, `RetryPolicy`, `GrantScope`, `GrantLedger`.

## Work Guidance

- **SILENT FAILURE TRAP**: After adding any `EventPayload` subclass, immediately add it to `Serialization.kt` `eventModule` block. Run `./gradlew check` to verify. Tests may pass without it but runtime replay will fail silently.
- `AnyMapSerializer` — custom serializer for `Map<String, Any?>`; use it for dynamic payloads, don't roll another.
- Event classes are `@Serializable data class` with no mutable state. No methods beyond data accessors.
- `RunBranchPushedEvent` records an optional server Git transport push only after it succeeds; its branch/base/head SHAs are observations, not values replay recalculates.
- `RepoMapEntry.descriptor` is a bounded source-purpose observation recorded with the repo map and used when constructing semantic L3 embeddings.
- Do not add domain logic to events. They are records, not actors.
- `EgressAllowlistProjection` — special projection kept in this module because it is used by both `core:toolintent` and `core:events` consumers; it is a shared cross-cutting projection.

## Verification

```bash
./gradlew :core:events:test --rerun-tasks
```

Tests in `testing/contracts/` (EventsTest, EventStoreContractTest) and `testing/replay/` (serialization round-trips, replay integration).

## Child DOX Index

No child AGENTS.md (leaf module).
