/**
 * @typedef {Object} FlowSession
 * @property {string} provider          the provider id the flow was started for
 * @property {string} state             CSRF nonce echoed on the callback
 * @property {string} [codeVerifier]    PKCE verifier (absent only when the provider rejects PKCE)
 * @property {string} [nonce]           OIDC replay nonce (OIDC providers only)
 * @property {string} [sessionBinding]  opaque binding to the initiating user's session
 * @property {string[]} [requestedScope] the scopes this flow requested — basis for the SCOPE_NARROWED warning
 * @property {number} createdAt         epoch ms — lets a store enforce a max age
 */
/**
 * @param {FlowSession} session
 * @returns {string}
 */
export function serializeSession(session: FlowSession): string;
/**
 * @param {string} serialized
 * @returns {FlowSession}
 */
export function deserializeSession(serialized: string): FlowSession;
export type FlowSession = {
    /**
     * the provider id the flow was started for
     */
    provider: string;
    /**
     * CSRF nonce echoed on the callback
     */
    state: string;
    /**
     * PKCE verifier (absent only when the provider rejects PKCE)
     */
    codeVerifier?: string | undefined;
    /**
     * OIDC replay nonce (OIDC providers only)
     */
    nonce?: string | undefined;
    /**
     * opaque binding to the initiating user's session
     */
    sessionBinding?: string | undefined;
    /**
     * the scopes this flow requested — basis for the SCOPE_NARROWED warning
     */
    requestedScope?: string[] | undefined;
    /**
     * epoch ms — lets a store enforce a max age
     */
    createdAt: number;
};