/**
 * Usage — token/cost accounting for a provider call (PROTOCOL §11).
 *
 * Emitted by the `usage` event (finer-grained than turn-end) and carried on `turn_end`.
 * All fields are optional except input/output so providers that don't report cache/cost
 * still validate.
 *
 * `provider` + `model` form the per-model/per-provider aggregation key the daemon's usage
 * log stamps onto each event (saga vr7kgx.20). Both optional + additive — providers that
 * omit them still validate; the aggregate falls back to a sentinel key.
 */
import { Type, type Static } from '@sinclair/typebox';

export const UsageSchema = Type.Object({
  input: Type.Integer(),
  output: Type.Integer(),
  cache_read: Type.Optional(Type.Integer()),
  cache_write: Type.Optional(Type.Integer()),
  cost: Type.Optional(Type.Number()),
  context_tokens: Type.Optional(Type.Integer()),
  model: Type.Optional(Type.String()),
  provider: Type.Optional(Type.String()),
});

export type Usage = Static<typeof UsageSchema>;