import type { CodexDiagnosticsLane, CodexDiagnosticsSink, CodexDiagnosticsTransport } from "./types.ts";
export declare const CODEX_BACKEND_TIMING_KEYS: string[];
export declare function createCodexRequestTiming(record: CodexDiagnosticsSink | undefined, now?: () => number, sessionId?: string): {
    requestId: string;
    readonly sessionRequestOrdinal: number | undefined;
    requestCounterProcessId: `${string}-${string}-${string}-${string}-${string}`;
    readonly nextAttempt: number;
    start(lane: CodexDiagnosticsLane, transport: CodexDiagnosticsTransport, measureOutput?: boolean): {
        attempt: number;
        sent(): void;
        observe(value: unknown): void;
        finish(outcome: "completed" | "failed" | "aborted"): void;
    };
};
export type CodexAttemptTiming = ReturnType<ReturnType<typeof createCodexRequestTiming>["start"]>;