type HarnessTurnRef = {
    readonly id: string;
    readonly sequence: number;
};
import type { TokenUsage } from "#shared/token-usage.js";
/** Emits a terminal `session.completed` outside a turn. */
export declare function emitTerminalSessionCompletionStep(input: {
    readonly sessionWritable: WritableStream<Uint8Array>;
    readonly serializedContext: Record<string, unknown>;
    /** The session's last turn, reported to channel handlers as `ctx.session.turn`. */
    readonly turn?: HarnessTurnRef;
    readonly usage: TokenUsage | undefined;
}): Promise<void>;
export {};