/**
 * A unified response interface that works across Node, Browser, and GAS.
 */
export interface PlatformResponse {
    ok: boolean;
    status: number;
    json<T = any>(): Promise<T>;
    text(): Promise<string>;
}
/**
 * Abstract interface for platform-specific functionality.
 * Allows the SDK to run in both Node.js, browser, and Google Apps Script environments.
 */
export interface Platform {
    /**
     * Saves a file to the platform's filesystem.
     */
    saveFile(filepath: string, data: string, encoding: 'base64', activityId?: string): Promise<void>;
    /**
     * Pauses execution for the specified duration.
     */
    sleep(ms: number): Promise<void>;
    /**
     * Creates a data URL for the given data.
     */
    createDataUrl(data: string, mimeType: string): string;
    /**
     * Unified network fetch.
     */
    fetch(input: string, init?: any): Promise<PlatformResponse>;
    /**
     * Unified crypto operations.
     */
    crypto: {
        /**
         * Generates a standard UUID v4.
         */
        randomUUID(): string;
        /**
         * Signs a string using HMAC-SHA256 and returns a Base64Url encoded string.
         * Used for minting Capability Tokens.
         */
        sign(text: string, secret: string): Promise<string>;
        /**
         * Verifies a signature.
         */
        verify(text: string, signature: string, secret: string): Promise<boolean>;
    };
    /**
     * Unified encoding/decoding operations.
     */
    encoding: {
        /**
         * Encodes a string to Base64URL format.
         * (URL-safe: '-' instead of '+', '_' instead of '/', no padding)
         */
        base64Encode(text: string): string;
        /**
         * Decodes a Base64URL encoded string.
         */
        base64Decode(text: string): string;
    };
    /**
     * Retrieves an environment variable or configuration value.
     *
     * @param key The name of the environment variable (e.g., "JULES_API_KEY").
     * @returns The value of the environment variable, or `undefined` if not set.
     */
    getEnv(key: string): string | undefined;
    readFile?(path: string): Promise<string>;
    writeFile?(path: string, content: string): Promise<void>;
    deleteFile?(path: string): Promise<void>;
}