fix(nextjs): skip custom browser tracing setup for bot user agents

Expose isBotUserAgent from the browser tracing integration and use it in the Next.js wrapper so bot user agents also skip the Next.js-specific router instrumentation path.

This is the smallest change to validate the fix. Longer term, we probably want a more general mechanism for integrations to skip their own setup and make that skip decision easy to downstream through wrappers and variants.

Co-Authored-By: GPT-5.4 <noreply@anthropic.com>

Author: logaretm

packages/browser/src/index.bundle.tracing.logs.metrics.ts

@@ -22,6 +22,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.bundle.tracing.replay.feedback.logs.metrics.ts

@@ -22,6 +22,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.bundle.tracing.replay.feedback.ts

@@ -27,6 +27,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.bundle.tracing.replay.logs.metrics.ts

@@ -22,6 +22,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.bundle.tracing.replay.ts

@@ -27,6 +27,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.bundle.tracing.ts

@@ -28,6 +28,7 @@ export {
 
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/index.ts

@@ -36,6 +36,7 @@ export { getFeedback, sendFeedback } from '@sentry-internal/feedback';
 export { defaultRequestInstrumentationOptions, instrumentOutgoingRequests } from './tracing/request';
 export {
   browserTracingIntegration,
+  isBotUserAgent,
   startBrowserTracingNavigationSpan,
   startBrowserTracingPageLoadSpan,
 } from './tracing/browserTracingIntegration';

packages/browser/src/tracing/browserTracingIntegration.ts

@@ -62,7 +62,7 @@ export const BROWSER_TRACING_INTEGRATION_ID = 'BrowserTracing';
 const BOT_USER_AGENT_RE =
   /Googlebot|Google-InspectionTool|Storebot-Google|Bingbot|Slurp|DuckDuckBot|Baiduspider|YandexBot|Facebot|facebookexternalhit|LinkedInBot|Twitterbot|Applebot/i;
 
-function _isBotUserAgent(): boolean {
+export function isBotUserAgent(): boolean {
   const nav = WINDOW.navigator as Navigator | undefined;
   if (!nav?.userAgent) {
     return false;
@@ -405,7 +405,7 @@ export const browserTracingIntegration = ((options: Partial<BrowserTracingOption
     ...options,
   };
 
-  const _isBot = _isBotUserAgent();
+  const _isBot = isBotUserAgent();
 
   let _collectWebVitals: undefined | (() => void);
   let lastInteractionTimestamp: number | undefined;

packages/nextjs/src/client/browserTracingIntegration.ts

@@ -1,5 +1,5 @@
 import type { Integration } from '@sentry/core';
-import { browserTracingIntegration as originalBrowserTracingIntegration } from '@sentry/react';
+import { browserTracingIntegration as originalBrowserTracingIntegration, isBotUserAgent } from '@sentry/react';
 import { nextRouterInstrumentNavigation, nextRouterInstrumentPageLoad } from './routing/nextRoutingInstrumentation';
 
 /**
@@ -29,6 +29,10 @@ export function browserTracingIntegration(
   return {
     ...browserTracingIntegrationInstance,
     afterAllSetup(client) {
+      if (isBotUserAgent()) {
+        return;
+      }
+
       // We need to run the navigation span instrumentation before the `afterAllSetup` hook on the normal browser
       // tracing integration because we need to ensure the order of execution is as follows:
       // Instrumentation to start span on RSC fetch request runs -> Instrumentation to put tracing headers from active span on fetch runs

packages/nextjs/test/clientSdk.test.ts

@@ -19,13 +19,15 @@ Object.defineProperty(global, 'addEventListener', { value: () => undefined, writ
 
 const originalGlobalDocument = WINDOW.document;
 const originalGlobalLocation = WINDOW.location;
+const originalNavigator = WINDOW.navigator;
 // eslint-disable-next-line @typescript-eslint/unbound-method
 const originalGlobalAddEventListener = WINDOW.addEventListener;
 
 afterAll(() => {
   // Clean up JSDom
   Object.defineProperty(WINDOW, 'document', { value: originalGlobalDocument });
   Object.defineProperty(WINDOW, 'location', { value: originalGlobalLocation });
+  Object.defineProperty(WINDOW, 'navigator', { value: originalNavigator, writable: true, configurable: true });
   Object.defineProperty(WINDOW, 'addEventListener', { value: originalGlobalAddEventListener });
 });
 
@@ -43,6 +45,7 @@ describe('Client init()', () => {
     getIsolationScope().clear();
     getCurrentScope().clear();
     getCurrentScope().setClient(undefined);
+    Object.defineProperty(WINDOW, 'navigator', { value: originalNavigator, writable: true, configurable: true });
   });
 
   it('inits the React SDK', () => {
@@ -160,6 +163,25 @@ describe('Client init()', () => {
         // @ts-expect-error Test setup for build-time flag
         delete globalThis.__SENTRY_TRACING__;
       });
+
+      it("doesn't run Next.js router instrumentation for bot user agents", () => {
+        Object.defineProperty(WINDOW, 'navigator', {
+          value: {
+            userAgent: 'Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)',
+          },
+          writable: true,
+          configurable: true,
+        });
+
+        const setIntervalSpy = vi.spyOn(globalThis, 'setInterval');
+
+        init({
+          dsn: TEST_DSN,
+          tracesSampleRate: 1.0,
+        });
+
+        expect(setIntervalSpy).not.toHaveBeenCalled();
+      });
     });
   });