/**
 * A custom replacer for `JSON.stringify` that converts specific types not natively supported
 * by the API into JSON-compatible formats.
 *
 * Supported conversions:
 * - `BigInt` → `{ "__bigint__": string }`
 * - `Principal` → `{ "__principal__": string }`
 * - `Uint8Array` → `{ "__uint8array__": number[] }`
 *
 * @param {string} _key - Ignored. Only provided for API compatibility.
 * @param {unknown} value - The value to transform before stringification.
 * @returns {unknown} The transformed value if it matches a known type, otherwise the original value.
 */
export declare const jsonReplacer: (_key: string, value: unknown) => unknown;
/**
 * A custom reviver for `JSON.parse` that reconstructs specific types from their JSON-encoded representations.
 *
 * This reverses the transformations applied by `jsonReplacer`, restoring the original types.
 *
 * Supported conversions:
 * - `{ "__bigint__": string }` → `BigInt`
 * - `{ "__principal__": string }` → `Principal`
 * - `{ "__uint8array__": number[] }` → `Uint8Array`
 *
 * @param {string} _key - Ignored but provided for API compatibility.
 * @param {unknown} value - The parsed value to transform.
 * @returns {unknown} The reconstructed value if it matches a known type, otherwise the original value.
 */
export declare const jsonReviver: (_key: string, value: unknown) => unknown;