/**
 * Persistent audit log — append-only JSONL file for request history.
 * Fire-and-forget writes, never blocks request path.
 */
import type { ProviderRequestDiagnostic } from './provider-error.js';
export interface AuditEntry {
    timestamp: string;
    requestId: string;
    model: string;
    servedBy?: string;
    inputTokens: number;
    outputTokens: number;
    durationMs: number;
    status: number;
    fallbackUsed: boolean;
    streaming: boolean;
    failure?: ProviderRequestDiagnostic;
}
/**
 * Append an audit entry. Fire-and-forget — errors are logged but never thrown.
 */
export declare function logAuditEntry(entry: AuditEntry): Promise<void>;
/**
 * Read recent audit entries.
 */
export declare function readAuditLog(count?: number): Promise<AuditEntry[]>;
/**
 * Get audit log file path (for testing/display).
 */
export declare function getAuditLogPath(): string;
