/**
 * @deprecated Use `getVercelOidcToken` instead.
 *
 * Gets the current OIDC token from the request context or the environment variable.
 *
 * Do not cache this value, as it is subject to change in production!
 *
 * This function is used to retrieve the OIDC token from the request context or the environment variable.
 * It checks for the `x-vercel-oidc-token` header in the request context and falls back to the `VERCEL_OIDC_TOKEN` environment variable if the header is not present.
 *
 * This function will not refresh the token if it is expired. For refreshing the token, use the @{link getVercelOidcToken} function.
 *
 * @returns {string} The OIDC token.
 * @throws {Error} If the `x-vercel-oidc-token` header is missing from the request context and the environment variable `VERCEL_OIDC_TOKEN` is not set.
 *
 * @example
 *
 * ```js
 * const token = getVercelOidcTokenSync();
 * console.log('OIDC Token:', token);
 * ```
 */
export declare function getVercelOidcTokenSync(): string;
