diff --git a/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-no-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-no-truncation.mjs
index 16eb0a6d74c6..5daa0a199d49 100644
--- a/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-no-truncation.mjs
+++ b/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-no-truncation.mjs
@@ -14,5 +14,12 @@ Sentry.init({
       enableTruncation: false,
     }),
   ],
+  beforeSendTransaction: event => {
+    // Filter out mock express server transactions
+    if (event.transaction.includes('/v1beta/')) {
+      return null;
+    }
+    return event;
+  },
   streamGenAiSpans: true,
 });
diff --git a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-message-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-message-truncation.mjs
index e6146214d7fe..d3cb34648f4a 100644
--- a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-message-truncation.mjs
+++ b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-message-truncation.mjs
@@ -1,48 +1,40 @@
-import { instrumentGoogleGenAIClient } from '@sentry/core';
+import { GoogleGenAI } from '@google/genai';
 import * as Sentry from '@sentry/node';
+import express from 'express';
 
-class MockGoogleGenerativeAI {
-  constructor(config) {
-    this.apiKey = config.apiKey;
+function startMockGoogleGenAIServer() {
+  const app = express();
+  app.use(express.json({ limit: '10mb' }));
 
-    this.models = {
-      generateContent: this._generateContent.bind(this),
-    };
-  }
-
-  async _generateContent() {
-    await new Promise(resolve => setTimeout(resolve, 10));
-
-    return {
-      response: {
-        text: () => 'Response to truncated messages',
-        usageMetadata: {
-          promptTokenCount: 10,
-          candidatesTokenCount: 15,
-          totalTokenCount: 25,
+  app.post('/v1beta/models/:model\\:generateContent', (req, res) => {
+    res.send({
+      candidates: [
+        {
+          content: { parts: [{ text: 'Response to truncated messages' }], role: 'model' },
+          finishReason: 'stop',
+          index: 0,
         },
-        candidates: [
-          {
-            content: {
-              parts: [{ text: 'Response to truncated messages' }],
-              role: 'model',
-            },
-            finishReason: 'STOP',
-          },
-        ],
-      },
-    };
-  }
+      ],
+      usageMetadata: { promptTokenCount: 10, candidatesTokenCount: 15, totalTokenCount: 25 },
+    });
+  });
+
+  return new Promise(resolve => {
+    const server = app.listen(0, () => {
+      resolve(server);
+    });
+  });
 }
 
 async function run() {
+  const server = await startMockGoogleGenAIServer();
+
   await Sentry.startSpan({ op: 'function', name: 'main' }, async () => {
-    const mockClient = new MockGoogleGenerativeAI({
+    const client = new GoogleGenAI({
       apiKey: 'mock-api-key',
+      httpOptions: { baseUrl: `http://localhost:${server.address().port}` },
     });
 
-    const client = instrumentGoogleGenAIClient(mockClient, { enableTruncation: true, recordInputs: true });
-
     // Test 1: Given an array of messages only the last message should be kept
     // The last message should be truncated to fit within the 20KB limit
     const largeContent1 = 'A'.repeat(15000); // ~15KB
@@ -80,6 +72,10 @@ async function run() {
       ],
     });
   });
+
+  await Sentry.flush(2000);
+
+  server.close();
 }
 
 run();
diff --git a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-no-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-no-truncation.mjs
index 13b271a23878..67ece6759577 100644
--- a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-no-truncation.mjs
+++ b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-no-truncation.mjs
@@ -1,35 +1,39 @@
-import { instrumentGoogleGenAIClient } from '@sentry/core';
+import { GoogleGenAI } from '@google/genai';
 import * as Sentry from '@sentry/node';
+import express from 'express';
 
-class MockGoogleGenerativeAI {
-  constructor(config) {
-    this.apiKey = config.apiKey;
-    this.models = {
-      generateContent: this._generateContent.bind(this),
-    };
-  }
-
-  async _generateContent() {
-    await new Promise(resolve => setTimeout(resolve, 10));
-    return {
-      response: {
-        text: () => 'Response',
-        usageMetadata: { promptTokenCount: 10, candidatesTokenCount: 5, totalTokenCount: 15 },
-        candidates: [
-          {
-            content: { parts: [{ text: 'Response' }], role: 'model' },
-            finishReason: 'STOP',
-          },
-        ],
-      },
-    };
-  }
+function startMockGoogleGenAIServer() {
+  const app = express();
+  app.use(express.json({ limit: '10mb' }));
+
+  app.post('/v1beta/models/:model\\:generateContent', (req, res) => {
+    res.send({
+      candidates: [
+        {
+          content: { parts: [{ text: 'Response' }], role: 'model' },
+          finishReason: 'stop',
+          index: 0,
+        },
+      ],
+      usageMetadata: { promptTokenCount: 10, candidatesTokenCount: 5, totalTokenCount: 15 },
+    });
+  });
+
+  return new Promise(resolve => {
+    const server = app.listen(0, () => {
+      resolve(server);
+    });
+  });
 }
 
 async function run() {
+  const server = await startMockGoogleGenAIServer();
+
   await Sentry.startSpan({ op: 'function', name: 'main' }, async () => {
-    const mockClient = new MockGoogleGenerativeAI({ apiKey: 'mock-api-key' });
-    const client = instrumentGoogleGenAIClient(mockClient, { enableTruncation: false, recordInputs: true });
+    const client = new GoogleGenAI({
+      apiKey: 'mock-api-key',
+      httpOptions: { baseUrl: `http://localhost:${server.address().port}` },
+    });
 
     // Long content that would normally be truncated
     const longContent = 'A'.repeat(50_000);
@@ -42,6 +46,10 @@ async function run() {
       ],
     });
   });
+
+  await Sentry.flush(2000);
+
+  server.close();
 }
 
 run();
diff --git a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-system-instructions.mjs b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-system-instructions.mjs
index d4081d052968..1a6f7d81d49e 100644
--- a/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-system-instructions.mjs
+++ b/dev-packages/node-integration-tests/suites/tracing/google-genai/scenario-system-instructions.mjs
@@ -1,41 +1,40 @@
-import { instrumentGoogleGenAIClient } from '@sentry/core';
+import { GoogleGenAI } from '@google/genai';
 import * as Sentry from '@sentry/node';
+import express from 'express';
 
-class MockGoogleGenAI {
-  constructor(config) {
-    this.apiKey = config.apiKey;
-    this.models = {
-      generateContent: async params => {
-        await new Promise(resolve => setTimeout(resolve, 10));
-        return {
-          response: {
-            text: () => 'Response',
-            modelVersion: params.model,
-            usageMetadata: {
-              promptTokenCount: 10,
-              candidatesTokenCount: 5,
-              totalTokenCount: 15,
-            },
-            candidates: [
-              {
-                content: {
-                  parts: [{ text: 'Response' }],
-                  role: 'model',
-                },
-                finishReason: 'STOP',
-              },
-            ],
-          },
-        };
-      },
-    };
-  }
+function startMockGoogleGenAIServer() {
+  const app = express();
+  app.use(express.json());
+
+  app.post('/v1beta/models/:model\\:generateContent', (req, res) => {
+    res.send({
+      candidates: [
+        {
+          content: { parts: [{ text: 'Response' }], role: 'model' },
+          finishReason: 'stop',
+          index: 0,
+        },
+      ],
+      modelVersion: req.params.model,
+      usageMetadata: { promptTokenCount: 10, candidatesTokenCount: 5, totalTokenCount: 15 },
+    });
+  });
+
+  return new Promise(resolve => {
+    const server = app.listen(0, () => {
+      resolve(server);
+    });
+  });
 }
 
 async function run() {
+  const server = await startMockGoogleGenAIServer();
+
   await Sentry.startSpan({ op: 'function', name: 'main' }, async () => {
-    const mockClient = new MockGoogleGenAI({ apiKey: 'mock-api-key' });
-    const client = instrumentGoogleGenAIClient(mockClient);
+    const client = new GoogleGenAI({
+      apiKey: 'mock-api-key',
+      httpOptions: { baseUrl: `http://localhost:${server.address().port}` },
+    });
 
     await client.models.generateContent({
       model: 'gemini-1.5-flash',
@@ -45,6 +44,10 @@ async function run() {
       contents: [{ role: 'user', parts: [{ text: 'Hello' }] }],
     });
   });
+
+  await Sentry.flush(2000);
+
+  server.close();
 }
 
 run();