import type { Api, AssistantMessageEventStream, Model, Usage } from "@earendil-works/pi-ai";
/**
 * Minimal push-based async event stream.
 *
 * Mirrors the contract the vendored client relies on: `push` before or after a
 * consumer attaches, `end` to terminate iteration, and `result` to await the
 * final assistant message.
 */
export declare function createAssistantMessageEventStream(): AssistantMessageEventStream;
/**
 * Fill in usage cost from the model's per-million-token rates.
 *
 * Kiro is subscription-metered and its catalog rates are zero, so in practice
 * this records zeros; it is kept faithful so the numbers stay correct if a
 * model ever does carry rates.
 */
export declare function calculateCost(model: Model<Api>, usage: Usage): void;