/**
 * Trace Recorder Middleware — Drop-in middleware for popular frameworks
 *
 * Provides Express middleware and Vercel AI SDK wrapper for automatic
 * agent trace recording.
 *
 * @example
 * ```typescript
 * // Express
 * import { agentProbeMiddleware } from '@neuzhou/agentprobe';
 * app.use(agentProbeMiddleware({ output: './traces' }));
 *
 * // Vercel AI SDK
 * import { withAgentProbe } from '@neuzhou/agentprobe';
 * const model = withAgentProbe(openai('gpt-4'));
 * ```
 */
import type { AgentTrace } from './types';
export interface MiddlewareOptions {
    output: string;
    prefix?: string;
    includeHeaders?: boolean;
    includeBody?: boolean;
    flushInterval?: number;
    maxTraces?: number;
    filter?: (req: any) => boolean;
    onTrace?: (trace: AgentTrace) => void;
}
export interface TraceBuffer {
    traces: AgentTrace[];
    outputDir: string;
    maxTraces: number;
}
/**
 * Create a trace buffer for batching trace writes.
 */
export declare function createTraceBuffer(outputDir: string, maxTraces?: number): TraceBuffer;
/**
 * Flush traces from buffer to disk.
 */
export declare function flushTraceBuffer(buffer: TraceBuffer): number;
/**
 * Add a trace to the buffer, auto-flushing if full.
 */
export declare function addToBuffer(buffer: TraceBuffer, trace: AgentTrace): boolean;
/**
 * Build a trace from an HTTP request/response cycle.
 */
export declare function buildTraceFromHTTP(method: string, url: string, requestBody: any, responseBody: any, durationMs: number, metadata?: Record<string, any>): AgentTrace;
/**
 * Create Express-compatible middleware for recording agent traces.
 */
export declare function agentProbeMiddleware(options: MiddlewareOptions): (req: any, res: any, next: any) => void;
/**
 * Wrapper configuration for AI SDK models.
 */
export interface WrapperOptions {
    output?: string;
    onTrace?: (trace: AgentTrace) => void;
    metadata?: Record<string, any>;
}
/**
 * Wrap a Vercel AI SDK model to record traces.
 * Returns a proxy that intercepts calls and records them.
 */
export declare function withAgentProbe(model: any, options?: WrapperOptions): any;
/**
 * Format middleware stats.
 */
export declare function formatMiddlewareStats(buffer: TraceBuffer): string;
//# sourceMappingURL=middleware.d.ts.map