code: function StormpathAccessTokenAuthenticator(client) {
    if (!(this instanceof StormpathAccessTokenAuthenticator)) {
      return new StormpathAccessTokenAuthenticator(client);
    }
  
    if (!(client instanceof Client)) {
      throw new Error('StormpathAccessTokenAuthenticator must be given a Stormpath client instance');
    }
  
    this.client = client;
    this.verifier = nJwt.createVerifier().withKeyResolver(tenantAdminKeyResolver.bind(null, client));
  }
docs: @class
  
  @constructor
  
  @description
  
  Creates an authenticator that can be used to validate access tokens that have
  been issued by a Stormpath Tenant, using API Keys created for accounts in that
  tenant's  "Stormpath Administrators" directory.  Access tokens can be issued
  with one of the following methods:
  
  - {@link OAuthClientCredentialsAuthenticator#authenticate OAuthClientCredentialsAuthenticator.authenticate()}
  - {@link OAuthPasswordGrantRequestAuthenticator#authenticate OAuthPasswordGrantRequestAuthenticator.authenticate()}
  - {@link OAuthStormpathTokenAuthenticator#authenticate OAuthStormpathTokenAuthenticator.authenticate()}
  
  @param {Client} client A constructed {@link Client} instance, which will be bound to
  the Stormpath Tenant in which access token tokens will be validated.
  
  @example
  var client = new stormpath.Client();
  
  var authenticator = new stormpath.StormpathAccessTokenAuthenticator(client);