Implementation: IMPLEMENTED (contract) · ENABLED (work-runtime ledger) · Exposure: INTERNAL. See status labels. A trace event is a small typed record of what happened at one step. Together with receipts it is enough to explain a run.

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Architecture contract

TraceEventV1 carries the envelope, an event_type, the primitive, capability, backend, model reference and tool where relevant, latency, token counts, cache hit, confidence, cost units, a status (STARTED, SUCCEEDED, FAILED, SKIPPED), the state versions before and after, receipt references and an error. Every node emits a receipt or trace event sufficient for semantic replay. Generated tokens need not be reproduced. The event-type vocabulary is not frozen; see event types.

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Current implementation

The work runtime records lifecycle and effect events in its internal ledger. Emitting the full TraceEventV1 from every primitive is not claimed.

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Availability

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Developer relevance

Emit an event at every boundary you own, with the state version and receipt references.