import type { MeterConfig, ModelPrice, SpendSummary, UsageEvent, UsageInput } from "./types.js";
export interface RecordResult {
    event: UsageEvent;
    price?: ModelPrice;
}
/** Price a usage input, append it to the ledger, and return the recorded event. */
export declare function recordUsage(input: UsageInput, config?: MeterConfig): RecordResult;
export declare function appendEvent(event: UsageEvent, config?: MeterConfig): void;
/** Read all ledger events, skipping any malformed lines. */
export declare function readEvents(config?: MeterConfig): UsageEvent[];
/** Aggregate events into totals for today / this month / by model / by session (local time). */
export declare function summarize(events: UsageEvent[], now?: Date): SpendSummary;
/** Total spend for a single session id. */
export declare function sessionSpend(events: UsageEvent[], sessionId: string): number;