import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
/**
 * Artifact-based completion guard: pi-interactive-subagents reports a
 * subagent "completed" on process exit even when its artifact was never
 * written. Completion notices arrive as extension steer messages, which
 * pass through the input hook. When the recorded artifact is missing or
 * empty, append a resume instruction so the parent never stalls waiting.
 * Also detect rate-limit-style errors in the same steer stream so the
 * adaptive spawn cadence can demote for the rest of this run.
 */
export declare function registerInputHook(pi: ExtensionAPI): void;