import type { HealthTransition } from "./health-store.js";
import { FallbackPumpAdmission } from "./stream-pump-admission.js";
import type { FailureClassification, OnRouterAttempt } from "./types.js";
export declare abstract class FallbackPumpObservability extends FallbackPumpAdmission {
    protected classifyError(error: unknown): FailureClassification;
    protected emitAttempt(idx: number, outcome: "success" | "failure" | "cancelled", error?: unknown, failure?: FailureClassification, willRetry?: boolean, healthTransition?: HealthTransition, inFlight?: number | undefined): void;
    protected emitSkippedAttempt(idx: number, reason: "concurrency" | "cooldown"): void;
    protected releaseActiveCandidate(): void;
    protected emitMaxAttemptSkips(startIndex: number): void;
    protected emitOrDeferSkippedAttempt(payload: Parameters<OnRouterAttempt>[0]): void;
    protected flushDeferredSkippedAttemptEvents(): void;
    protected discardDeferredConcurrencySkip(idx: number): void;
    protected emitCancelledPendingAttempt(): void;
    protected beginDeferredAdmission(retry: boolean, withinAttemptBudget: boolean, nextIdx: number): void;
    protected endDeferredAdmission(): void;
}