This page covers how token counts and costs are recorded and added up per run or per workflow. The project records only numbers that a provider or your own code supplies, and it never guesses a missing cost.
usage.recorded reports measurements observed by an adapter. AgenTrust
Telemetry does not count tokens, resolve model prices, or infer a missing cost.
Use usage_record() for call-level facts and supply CostObservation only when
the provider, caller, or a named price resolver has produced a cost. An unknown
price is represented by the absence of cost, never by a synthetic zero.
UsageAccumulator accepts model_call leaves only, deduplicates them by
event_id, and can create agent_run or workflow_run rollups. Each rollup
contains the number of source events and per-field coverage counts. Consumers
can therefore distinguish a complete total from the sum of only the observations
that happened to include a field. Mixed-currency cost rollups are rejected.
Rollups are new telemetry facts. A metrics pipeline should select either leaf events or rollup events for a given aggregation query; adding both double counts.