/**
 * A read-only snapshot of accumulated spend. Returned by
 * {@link CostAccumulator.snapshot} so a report can render the total without
 * holding a mutable reference to the accumulator.
 */
export interface CostSnapshot {
    /** Total cost in US dollars summed across every recorded call. */
    totalUsd: number;
    /** Number of provider calls recorded (including zero-cost cache hits). */
    calls: number;
}
/**
 * Accumulates the per-call `costUsd` of provider results into a single per-run
 * total. Cache hits (cost `0`) are still counted as calls so the call count
 * reflects how many generations the pipeline requested, not how many hit the
 * network.
 */
export declare class CostAccumulator {
    #private;
    /**
     * Record one provider call's cost. Negative costs are rejected (no provider
     * reports a negative charge; a negative value signals a bug upstream and
     * must not silently understate the run total). Resolves nothing; mutates the
     * running total in place.
     */
    add(costUsd: number): void;
    /** Total accumulated cost in US dollars across all recorded calls. */
    get totalUsd(): number;
    /** Number of provider calls recorded so far. */
    get calls(): number;
    /** A plain read-only snapshot suitable for handing to a reporter. */
    snapshot(): CostSnapshot;
    /** Reset the accumulator to its initial empty state (for reuse across runs). */
    reset(): void;
}