diff --git a/src/main/java/codes/thischwa/cf/CfBasicHttpClient.java b/src/main/java/codes/thischwa/cf/CfBasicHttpClient.java
index 13c165a..4a87f8e 100644
--- a/src/main/java/codes/thischwa/cf/CfBasicHttpClient.java
+++ b/src/main/java/codes/thischwa/cf/CfBasicHttpClient.java
@@ -35,15 +35,22 @@ abstract class CfBasicHttpClient {
   private final String baseUrl;
   private final String authEmail;
   private final String authKey;
-  private final String authToken;
 
   private final ObjectMapper objectMapper;
 
-  CfBasicHttpClient(String baseUrl, String authEmail, String authKey, String authToken) {
+  CfBasicHttpClient(String baseUrl, String authEmail, String authKey) {
+    if (baseUrl == null || baseUrl.isBlank()) {
+      throw new IllegalArgumentException("Base URL must not be null or blank!");
+    }
+    if (authEmail == null || authEmail.isBlank()) {
+      throw new IllegalArgumentException("Authentication email must not be null or blank!");
+    }
+    if (authKey == null || authKey.isBlank()) {
+      throw new IllegalArgumentException("Authentication key must not be null or blank!");
+    }
     this.baseUrl = baseUrl;
     this.authEmail = authEmail;
     this.authKey = authKey;
-    this.authToken = authToken;
     this.objectMapper = initObjectMapper();
   }
 
@@ -67,7 +74,6 @@ abstract class CfBasicHttpClient {
                   HttpHeaders.CONTENT_TYPE, ContentType.APPLICATION_JSON.getMimeType());
               request.addHeader("X-Auth-Email", authEmail);
               request.addHeader("X-Auth-Key", authKey);
-              request.addHeader("X-Auth-Token", authToken);
             })
         .build();
   }
diff --git a/src/main/java/codes/thischwa/cf/CfDnsClient.java b/src/main/java/codes/thischwa/cf/CfDnsClient.java
index ae87349..580a411 100644
--- a/src/main/java/codes/thischwa/cf/CfDnsClient.java
+++ b/src/main/java/codes/thischwa/cf/CfDnsClient.java
@@ -53,10 +53,9 @@ public class CfDnsClient extends CfBasicHttpClient {
    *     authentication.
    * @param authKey The API key of the Cloudflare account, used as part of the authentication
    *     process.
-   * @param authToken The API token for accessing specific resources within the Cloudflare account.
    */
-  public CfDnsClient(String authEmail, String authKey, String authToken) {
-    this(DEFAULT_BASEURL, authEmail, authKey, authToken);
+  public CfDnsClient(String authEmail, String authKey) {
+    this(DEFAULT_BASEURL, authEmail, authKey);
   }
 
   /**
@@ -67,10 +66,9 @@ public class CfDnsClient extends CfBasicHttpClient {
    *     authentication.
    * @param authKey The API key of the Cloudflare account, used as part of the authentication
    *     process.
-   * @param authToken The API token for accessing specific resources within the Cloudflare account.
    */
-  public CfDnsClient(String baseUrl, String authEmail, String authKey, String authToken) {
-    this(true, baseUrl, authEmail, authKey, authToken);
+  public CfDnsClient(String baseUrl, String authEmail, String authKey) {
+    this(true, baseUrl, authEmail, authKey);
   }
 
   /**
@@ -82,15 +80,13 @@ public class CfDnsClient extends CfBasicHttpClient {
    * @param baseUrl The base URL for the Cloudflare API endpoint.
    * @param authEmail The email associated with the Cloudflare account for authentication.
    * @param authKey The API key for authenticating the client with Cloudflare services.
-   * @param authToken The authentication token used for authorized access to Cloudflare API.
    */
   public CfDnsClient(
       boolean emptyResultThrowsException,
       String baseUrl,
       String authEmail,
-      String authKey,
-      String authToken) {
-    super(baseUrl, authEmail, authKey, authToken);
+      String authKey) {
+    super(baseUrl, authEmail, authKey);
     this.emptyResultThrowsException = emptyResultThrowsException;
   }
 
diff --git a/src/test/java/codes/thischwa/cf/CfClientTest.java b/src/test/java/codes/thischwa/cf/CfClientTest.java
index 3373b6e..963cb80 100644
--- a/src/test/java/codes/thischwa/cf/CfClientTest.java
+++ b/src/test/java/codes/thischwa/cf/CfClientTest.java
@@ -21,9 +21,8 @@ public class CfClientTest {
 
   private final String email = System.getenv("API_EMAIL");
   private final String apiKey = System.getenv("API_KEY");
-  private final String apiToken = System.getenv("API_TOKEN");
 
-  private final CfDnsClient client = new CfDnsClient(email, apiKey, apiToken);
+  private final CfDnsClient client = new CfDnsClient(email, apiKey);
 
   @Test
   void testList() throws Exception {