import { Context, TextMapGetter, TextMapPropagator, TextMapSetter } from '@opentelemetry/api';
export declare const X_B3_TRACE_ID = "x-b3-traceid";
export declare const X_B3_SPAN_ID = "x-b3-spanid";
export declare const X_B3_SAMPLED = "x-b3-sampled";
export declare const X_B3_PARENT_SPAN_ID = "x-b3-parentspanid";
export declare const X_B3_FLAGS = "x-b3-flags";
export declare function parseHeader(header: unknown): any;
/**
 * Propagator for the B3 multiple-header HTTP format.
 * Based on: https://github.com/openzipkin/b3-propagation
 */
export declare class B3MultiPropagator implements TextMapPropagator {
    inject(context: Context, carrier: unknown, setter: TextMapSetter): void;
    extract(context: Context, carrier: unknown, getter: TextMapGetter): Context;
    fields(): string[];
}