vtcode-exec-events

Root AGENTS.md | Authoritative ThreadEvent contract. All runtime events flow through this crate.

Key Types

ThreadEvent enum — the single event type (serde-tagged) | VersionedThreadEvent wrapper with schema version | EventEmitter trait | Usage token accounting | ThreadItem + ThreadItemDetails item taxonomy | EVENT_SCHEMA_VERSION semver string

ThreadEvent Variants

thread.started | thread.completed | thread.compact_boundary | turn.started | turn.completed | turn.failed | item.started | item.updated | item.completed | plan.delta | error

Rules

• Do not invent parallel event types. Extend ThreadEvent and ThreadItemDetails enums.
• EVENT_SCHEMA_VERSION must be bumped on breaking schema changes.
• EventEmitter trait has a blanket FnMut(&ThreadEvent) impl.
• Feature-gated emitters: telemetry-log (LogEmitter), telemetry-tracing (TracingEmitter), schema-export (JSON Schema), serde-json (JSON helpers).
• atif/ module exports ATIF (Agent Trace Interchange Format).
• trace/ module implements Agent Trace spec for AI code attribution.

Gotchas

• vtcode-core::exec::events re-exports these types — consumers should use that path, not depend on this crate directly.
• HarnessEventItem uses HarnessEventKind enum — adding variants requires schema version bump.