import type { StreamDelta } from "../shared/types.js";
export declare function normalizeBlockDeltaForTurn(delta: StreamDelta, turnStartedAt: number): {
    ok: true;
    delta: StreamDelta;
} | {
    ok: false;
    error: string;
};
/**
 * Fold a streamed text/text_snapshot delta into the accumulated partial text.
 * Incremental text appends; an authoritative snapshot always replaces.
 */
export declare function foldPartialText(curText: string, delta: StreamDelta): string;
export interface PartialStreamWriter {
    persist(delta: StreamDelta): void;
    finish(): void;
}
/** Persist one engine turn's live stream as coalesced partial transcript rows. */
export declare function createPartialStreamWriter(sessionId: string): PartialStreamWriter;
//# sourceMappingURL=partial-stream.d.ts.map