export interface BoundedBufferOptions {
    headLimitBytes?: number;
    tailLimitBytes?: number;
}
export interface BoundedBuffer {
    /** Retains a chunk, dropping bytes from the middle once both ends are full. */
    append: (chunk: Buffer) => void;
    /** Renders the retained bytes, with a marker naming the dropped count standing in for what was dropped. */
    toBuffer: () => Buffer;
}
/**
 * Creates an accumulator that retains the first and last bytes it is fed and drops the middle.
 * Both ends are kept because a failing command's first error and its trailing summary each carry signal
 * that the other end does not.
 */
export declare function createBoundedBuffer(options?: BoundedBufferOptions): BoundedBuffer;