diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1b5a584..75998c7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 2.4.1
+
+* fixed entrypoint
+* fixed configuration validation
+
 ## 2.4.0
 
 * added new custom metric fields
diff --git a/package.json b/package.json
index 3d836f0..e2a839a 100644
--- a/package.json
+++ b/package.json
@@ -1,9 +1,9 @@
 {
   "name": "pirsch-sdk",
-  "version": "2.4.0",
-  "description": "JavaScript client SDK for Pirsch.",
-  "main": "index.js",
-  "types": "index.d.ts",
+  "version": "2.4.1",
+  "description": "TypeScript/JavaScript client SDK for Pirsch.",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
   "scripts": {
     "build": "rm -rf dist && tsc",
     "watch": "tsc --watch",
diff --git a/src/common.ts b/src/common.ts
index ef3cbe1..8be5ac7 100644
--- a/src/common.ts
+++ b/src/common.ts
@@ -8,8 +8,8 @@ import {
 } from "./constants";
 
 export abstract class PirschCommon {
-    protected assertOauthCredentials({ clientId, clientSecret }: { clientId: string; clientSecret: string }) {
-        if (clientId.length !== PIRSCH_CLIENT_ID_LENGTH) {
+    protected assertOauthCredentials({ clientId, clientSecret }: { clientId?: string; clientSecret: string }) {
+        if (clientId?.length !== PIRSCH_CLIENT_ID_LENGTH) {
             throw new Error(`Invalid Client ID, should be of length '${PIRSCH_CLIENT_ID_LENGTH}'!`);
         }
 
diff --git a/src/core.ts b/src/core.ts
index a4ddeb5..b7afe04 100644
--- a/src/core.ts
+++ b/src/core.ts
@@ -86,7 +86,7 @@ export abstract class PirschCoreClient extends PirschCommon {
             this.assertAccessTokenCredentials({ accessToken });
             this.accessToken = accessToken;
             this.accessMode = "access-token";
-        } else if ("clientId" in configuration && "clientSecret" in configuration) {
+        } else if ("clientId" in configuration || "clientSecret" in configuration) {
             const { clientId, clientSecret } = configuration;
             this.assertOauthCredentials({ clientId, clientSecret });
             this.clientId = clientId;
diff --git a/src/types.ts b/src/types.ts
index b82ed52..d42c2e7 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -25,7 +25,7 @@ export interface PirschOAuthClientConfig extends PirschClientConfigBase {
     /**
      * The OAuth client ID
      */
-    clientId: string;
+    clientId?: string;
     /**
      * The OAuth client secret
      */