import type { TelemetryExporter } from './telemetry.js';
/**
 * Optional Langfuse exporter. Adapts Fabric's `TelemetrySpan` shape to
 * Langfuse's tracing API. The Langfuse client is provided by the caller —
 * we don't take a hard dependency.
 *
 * Install peer dep:
 * ```sh
 * npm install langfuse
 * ```
 *
 * Usage:
 * ```ts
 * import { Langfuse } from 'langfuse';
 * import { langfuseExporter } from '@fabric-harness/sdk';
 *
 * const langfuse = new Langfuse({ publicKey, secretKey, baseUrl });
 * const exporter = langfuseExporter({ client: langfuse, defaultName: 'my-agent' });
 *
 * await exporter.export({
 *   name: 'fabric.tool_end',
 *   startedAt: '...',
 *   endedAt: '...',
 *   durationMs: 42,
 *   attributes: { 'fabric.tool': 'bash' },
 * });
 * ```
 */
export interface LangfuseClientLike {
    trace?(input: {
        name?: string;
        sessionId?: string;
        metadata?: Record<string, unknown>;
    }): {
        id?: string;
        span?(input: LangfuseSpanInput): {
            id?: string;
        };
    };
    span?(input: LangfuseSpanInput): {
        id?: string;
    };
    /** Optional flush hook (Langfuse has `flushAsync()` / `flush()`). */
    flushAsync?(): Promise<void>;
    flush?(): void | Promise<void>;
}
interface LangfuseSpanInput {
    name: string;
    startTime?: Date;
    endTime?: Date;
    metadata?: Record<string, unknown>;
}
export interface LangfuseExporterOptions {
    client: LangfuseClientLike;
    /** Default span name used when the telemetry span lacks one. */
    defaultName?: string;
    /** Always-on attributes added to every span. */
    attributes?: Record<string, string | number | boolean>;
    /** When true, calls `client.flushAsync()` (or `flush()`) after each export. */
    flushOnExport?: boolean;
}
export declare function langfuseExporter(options: LangfuseExporterOptions): TelemetryExporter;
export {};
//# sourceMappingURL=langfuse.d.ts.map