diff --git a/client.js b/client.js
index c2b9cd6e46f9f66f901af259661bc2d2f8b38936..9b6b3af1a6573e1ccaf3a1c5f41b48df198cbbe0 100644
--- a/client.js
+++ b/client.js
@@ -26,7 +26,7 @@ Object.defineProperty(exports, "__esModule", { value: true });
 exports.AnthropicVertex = exports.BaseAnthropic = void 0;
 const client_1 = require("@anthropic-ai/sdk/client");
 const Resources = __importStar(require("@anthropic-ai/sdk/resources/index"));
-const google_auth_library_1 = require("google-auth-library");
+// const google_auth_library_1 = require("google-auth-library");
 const env_1 = require("./internal/utils/env.js");
 const values_1 = require("./internal/utils/values.js");
 const headers_1 = require("./internal/headers.js");
@@ -56,7 +56,7 @@ class AnthropicVertex extends client_1.BaseAnthropic {
             throw new Error('No region was given. The client should be instantiated with the `region` option or the `CLOUD_ML_REGION` environment variable should be set.');
         }
         super({
-            baseURL: baseURL || `https://${region}-aiplatform.googleapis.com/v1`,
+            baseURL: baseURL || (region === 'global' ? 'https://aiplatform.googleapis.com/v1' : `https://${region}-aiplatform.googleapis.com/v1`),
             ...opts,
         });
         this.messages = makeMessagesResource(this);
@@ -64,22 +64,22 @@ class AnthropicVertex extends client_1.BaseAnthropic {
         this.region = region;
         this.projectId = projectId;
         this.accessToken = opts.accessToken ?? null;
-        this._auth =
-            opts.googleAuth ?? new google_auth_library_1.GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
-        this._authClientPromise = this._auth.getClient();
+        // this._auth =
+        //    opts.googleAuth ?? new google_auth_library_1.GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
+        // this._authClientPromise = this._auth.getClient();
     }
     validateHeaders() {
         // auth validation is handled in prepareOptions since it needs to be async
     }
-    async prepareOptions(options) {
-        const authClient = await this._authClientPromise;
-        const authHeaders = await authClient.getRequestHeaders();
-        const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
-        if (!this.projectId && projectId) {
-            this.projectId = projectId;
-        }
-        options.headers = (0, headers_1.buildHeaders)([authHeaders, options.headers]);
-    }
+        // async prepareOptions(options) {
+        //     const authClient = await this._authClientPromise;
+        //     const authHeaders = await authClient.getRequestHeaders();
+        //     const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
+        //     if (!this.projectId && projectId) {
+        //         this.projectId = projectId;
+        //     }
+        //     options.headers = (0, headers_1.buildHeaders)([authHeaders, options.headers]);
+        // }
     buildRequest(options) {
         if ((0, values_1.isObj)(options.body)) {
             // create a shallow copy of the request body so that code that mutates it later
diff --git a/client.mjs b/client.mjs
index 70274cbf38f69f87cbcca9567e77e4a7b938cf90..4dea954b6f4afad565663426b7adfad5de973a7d 100644
--- a/client.mjs
+++ b/client.mjs
@@ -1,6 +1,6 @@
 import { BaseAnthropic } from '@anthropic-ai/sdk/client';
 import * as Resources from '@anthropic-ai/sdk/resources/index';
-import { GoogleAuth } from 'google-auth-library';
+// import { GoogleAuth } from 'google-auth-library';
 import { readEnv } from "./internal/utils/env.mjs";
 import { isObj } from "./internal/utils/values.mjs";
 import { buildHeaders } from "./internal/headers.mjs";
@@ -29,7 +29,7 @@ export class AnthropicVertex extends BaseAnthropic {
             throw new Error('No region was given. The client should be instantiated with the `region` option or the `CLOUD_ML_REGION` environment variable should be set.');
         }
         super({
-            baseURL: baseURL || `https://${region}-aiplatform.googleapis.com/v1`,
+            baseURL: baseURL || (region === 'global' ? 'https://aiplatform.googleapis.com/v1' : `https://${region}-aiplatform.googleapis.com/v1`),
             ...opts,
         });
         this.messages = makeMessagesResource(this);
@@ -37,22 +37,22 @@ export class AnthropicVertex extends BaseAnthropic {
         this.region = region;
         this.projectId = projectId;
         this.accessToken = opts.accessToken ?? null;
-        this._auth =
-            opts.googleAuth ?? new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
-        this._authClientPromise = this._auth.getClient();
+        // this._auth =
+        //    opts.googleAuth ?? new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
+        //this._authClientPromise = this._auth.getClient();
     }
     validateHeaders() {
         // auth validation is handled in prepareOptions since it needs to be async
     }
-    async prepareOptions(options) {
-        const authClient = await this._authClientPromise;
-        const authHeaders = await authClient.getRequestHeaders();
-        const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
-        if (!this.projectId && projectId) {
-            this.projectId = projectId;
-        }
-        options.headers = buildHeaders([authHeaders, options.headers]);
-    }
+    // async prepareOptions(options) {
+    //     const authClient = await this._authClientPromise;
+    //     const authHeaders = await authClient.getRequestHeaders();
+    //     const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
+    //     if (!this.projectId && projectId) {
+    //         this.projectId = projectId;
+    //     }
+    //     options.headers = buildHeaders([authHeaders, options.headers]);
+    // }
     buildRequest(options) {
         if (isObj(options.body)) {
             // create a shallow copy of the request body so that code that mutates it later
diff --git a/src/client.ts b/src/client.ts
index a6f9c6be65e4189f4f9601fb560df3f68e7563eb..37b1ad2802e3ca0dae4ca35f9dcb5b22dcf09796 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -12,22 +12,22 @@ export { BaseAnthropic } from '@anthropic-ai/sdk/client';
 const DEFAULT_VERSION = 'vertex-2023-10-16';
 const MODEL_ENDPOINTS = new Set<string>(['/v1/messages', '/v1/messages?beta=true']);
 
-export type ClientOptions = Omit<CoreClientOptions, 'apiKey' | 'authToken'> & {
-  region?: string | null | undefined;
-  projectId?: string | null | undefined;
-  accessToken?: string | null | undefined;
-
-  /**
-   * Override the default google auth config using the
-   * [google-auth-library](https://www.npmjs.com/package/google-auth-library) package.
-   *
-   * Note that you'll likely have to set `scopes`, e.g.
-   * ```ts
-   * new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' })
-   * ```
-   */
-  googleAuth?: GoogleAuth | null | undefined;
-};
+// export type ClientOptions = Omit<CoreClientOptions, 'apiKey' | 'authToken'> & {
+//   region?: string | null | undefined;
+//   projectId?: string | null | undefined;
+//   accessToken?: string | null | undefined;
+
+//   /**
+//    * Override the default google auth config using the
+//    * [google-auth-library](https://www.npmjs.com/package/google-auth-library) package.
+//    *
+//    * Note that you'll likely have to set `scopes`, e.g.
+//    * ```ts
+//    * new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' })
+//    * ```
+//    */
+//   googleAuth?: GoogleAuth | null | undefined;
+// };
 
 export class AnthropicVertex extends BaseAnthropic {
   region: string;
@@ -74,9 +74,9 @@ export class AnthropicVertex extends BaseAnthropic {
     this.projectId = projectId;
     this.accessToken = opts.accessToken ?? null;
 
-    this._auth =
-      opts.googleAuth ?? new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
-    this._authClientPromise = this._auth.getClient();
+    // this._auth =
+    //   opts.googleAuth ?? new GoogleAuth({ scopes: 'https://www.googleapis.com/auth/cloud-platform' });
+    // this._authClientPromise = this._auth.getClient();
   }
 
   messages: MessagesResource = makeMessagesResource(this);
@@ -86,17 +86,17 @@ export class AnthropicVertex extends BaseAnthropic {
     // auth validation is handled in prepareOptions since it needs to be async
   }
 
-  protected override async prepareOptions(options: FinalRequestOptions): Promise<void> {
-    const authClient = await this._authClientPromise;
+  // protected override async prepareOptions(options: FinalRequestOptions): Promise<void> {
+  //   const authClient = await this._authClientPromise;
 
-    const authHeaders = await authClient.getRequestHeaders();
-    const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
-    if (!this.projectId && projectId) {
-      this.projectId = projectId;
-    }
+  //   const authHeaders = await authClient.getRequestHeaders();
+  //   const projectId = authClient.projectId ?? authHeaders['x-goog-user-project'];
+  //   if (!this.projectId && projectId) {
+  //     this.projectId = projectId;
+  //   }
 
-    options.headers = buildHeaders([authHeaders, options.headers]);
-  }
+  //   options.headers = buildHeaders([authHeaders, options.headers]);
+  // }
 
   override buildRequest(options: FinalRequestOptions): {
     req: FinalizedRequestInit;