Impact and usage

The metric dictionary and source events, impact contracts with baselines and cohorts, and usage and cost allocated from SSO.

• Metrics and sourcesWhere impact events come from, the event vocabulary, signed webhooks and CSV imports, the versioned metric dictionary, and how every figure keeps its source and denominators.
• Impact contractsThe agreement that makes an impact claim checkable, with its baseline, windows, metrics, guardrails, comparison method, stated causal limits and benefit classification, and the reports and alerts that follow it.
• Usage and costWhat Bookbag SSO reports about EvalBook's model usage, how EvalBook's own calls are recorded, and how charges are allocated to work as figures labelled "allocated from SSO usage", never as an invoice.