export interface AddClientAuthenticationPayload {
    client_id?: string;
    client_secret?: string;
    client_assertion?: string;
    client_assertion_type?: string;
    [key: string]: any;
}
interface AddClientAuthenticationOptions {
    payload: AddClientAuthenticationPayload;
    domain: string;
    clientId: string;
    required?: boolean;
    clientAssertionSigningKey?: string;
    clientAssertionSigningAlg?: string;
    clientSecret?: string;
    useMTLS?: boolean;
}
/**
 * Adds client authentication, if available, to the provided payload.
 *
 * Adds `client_secret` for Client Secret Post token endpoint auth method (the SDK doesn't use Client Secret Basic)
 * Adds `client_assertion` and `client_assertion_type` for Private Key JWT token endpoint auth method.
 *
 * If `clientAssertionSigningKey` is provided it takes precedent over `clientSecret` .
 */
export declare const addClientAuthentication: ({ payload, domain, clientId, clientAssertionSigningKey, clientAssertionSigningAlg, clientSecret, useMTLS, }: AddClientAuthenticationOptions) => Promise<Record<string, unknown>>;
export {};