/**
 * Fire-and-forget cost telemetry from a subprocess to its parent, so
 * parent-side cost guards see child LLM spend live (see
 * docs/superpowers/specs/2026-07-02-subprocess-cost-telemetry-design.md).
 *
 * Deliberately dependency-light (the subprocessRunInfo.ts layering
 * pattern — the only import IS subprocessRunInfo, itself dependency-free):
 * `StateStack.billCharge` calls this on every paid charge, and stateStack
 * must not import ipc.ts.
 *
 * Never blocks and never throws: there is no reply, no listener, and a
 * dead channel is swallowed — the bootstrap disconnect watchdog is about
 * to reap this process anyway.
 */
export type IpcTelemetryMessage = {
    type: "telemetry";
    costUsd: number;
};
/** The wire contract for a billable cost: a positive finite number.
 * Shared by the sender and the parent-side handler so both ends of the
 * channel enforce the same rule (the receiving side matters more — the
 * child is the less-trusted party). */
export declare function isPayableCost(costUsd: unknown): costUsd is number;
export declare function sendCostTelemetryToParent(costUsd: number): void;