export declare const requestInstrumentationBodyKey = "cruddlRequestInstrumentation";
export type RequestInstrumentationPhase = 'queuing' | 'socketInit' | 'lookup' | 'connecting' | 'waiting' | 'receiving';
export interface RequestInstrumentation {
    onPhaseEnded(phase: RequestInstrumentationPhase): void;
    readonly cancellationToken: Promise<void>;
    /**
     * is set to true by custom-connection on cancellationToken.then() to allow synchronous access to the cancellation state
     */
    isCancelled?: boolean;
}