feat(core): Disable gen_ai message truncation by default when streamGenAiSpans is enabled

andreiborza · andreiborza · commit fd07b23dc005 · 2026-06-17T13:22:05.000+02:00
Setting `streamGenAiSpans: true` now disables gen_ai input truncation by default.
Because gen_ai spans are sent as v2 span envelope items, they are not subject to
the transaction payload-size limits that truncation works around.

Set `enableTruncation: true` on the respective AI integration to opt back into
truncation.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,6 +4,14 @@
 
 - "You miss 100 percent of the chances you don't take. — Wayne Gretzky" — Michael Scott
 
+### Important Changes
+
+- feat(core): Disable gen_ai message truncation by default when `streamGenAiSpans` is enabled
+
+  Setting `streamGenAiSpans: true` now disables gen_ai input truncation by default. Because gen_ai spans are sent as v2 span envelope items, they are not subject to the transaction payload-size limits that truncation works around.
+
+  Set `enableTruncation: true` on the respective AI integration to opt back into truncation.
+
 ## 10.58.0
 
 ### Important Changes
diff --git a/dev-packages/node-integration-tests/suites/tracing/anthropic/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/anthropic/instrument-with-truncation.mjs
@@ -0,0 +1,19 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.anthropicAIIntegration({ enableTruncation: true })],
+  beforeSendTransaction: event => {
+    // Filter out mock express server transactions
+    if (event.transaction.includes('/anthropic/v1/')) {
+      return null;
+    }
+    return event;
+  },
+  streamGenAiSpans: true,
+});
diff --git a/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts b/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts
@@ -606,7 +606,7 @@ describe('Anthropic integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'scenario-message-truncation.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit - keeps only last message and crops it', async () => {
         await createRunner()
@@ -659,51 +659,56 @@ describe('Anthropic integration', () => {
     },
   );
 
-  createEsmAndCjsTests(__dirname, 'scenario-media-truncation.mjs', 'instrument-with-pii.mjs', (createRunner, test) => {
-    test('truncates media attachment, keeping all other details', async () => {
-      const expectedMediaMessages = JSON.stringify([
-        {
-          role: 'user',
-          content: [
-            {
-              type: 'image',
-              source: {
-                type: 'base64',
-                media_type: 'image/png',
-                data: '[Blob substitute]',
+  createEsmAndCjsTests(
+    __dirname,
+    'scenario-media-truncation.mjs',
+    'instrument-with-truncation.mjs',
+    (createRunner, test) => {
+      test('truncates media attachment, keeping all other details', async () => {
+        const expectedMediaMessages = JSON.stringify([
+          {
+            role: 'user',
+            content: [
+              {
+                type: 'image',
+                source: {
+                  type: 'base64',
+                  media_type: 'image/png',
+                  data: '[Blob substitute]',
+                },
               },
-            },
-          ],
-        },
-      ]);
-      await createRunner()
-        .ignore('event')
-        .expect({
-          transaction: {
-            transaction: 'main',
+            ],
           },
-        })
-        .expect({
-          span: container => {
-            expect(container.items).toHaveLength(1);
-            const [firstSpan] = container.items;
+        ]);
+        await createRunner()
+          .ignore('event')
+          .expect({
+            transaction: {
+              transaction: 'main',
+            },
+          })
+          .expect({
+            span: container => {
+              expect(container.items).toHaveLength(1);
+              const [firstSpan] = container.items;
 
-            // [0] messages.create with media attachment — image data replaced, other fields preserved
-            expect(firstSpan!.name).toBe('chat claude-3-haiku-20240307');
-            expect(firstSpan!.status).toBe('ok');
-            expect(firstSpan!.attributes[GEN_AI_INPUT_MESSAGES_ATTRIBUTE].value).toBe(expectedMediaMessages);
-            expect(firstSpan!.attributes[GEN_AI_OPERATION_NAME_ATTRIBUTE].value).toBe('chat');
-            expect(firstSpan!.attributes['sentry.op'].value).toBe('gen_ai.chat');
-            expect(firstSpan!.attributes['sentry.origin'].value).toBe('auto.ai.anthropic');
-            expect(firstSpan!.attributes[GEN_AI_SYSTEM_ATTRIBUTE].value).toBe('anthropic');
-            expect(firstSpan!.attributes[GEN_AI_REQUEST_MODEL_ATTRIBUTE].value).toBe('claude-3-haiku-20240307');
-            expect(firstSpan!.attributes[GEN_AI_INPUT_MESSAGES_ORIGINAL_LENGTH_ATTRIBUTE].value).toBe(2);
-          },
-        })
-        .start()
-        .completed();
-    });
-  });
+              // [0] messages.create with media attachment — image data replaced, other fields preserved
+              expect(firstSpan!.name).toBe('chat claude-3-haiku-20240307');
+              expect(firstSpan!.status).toBe('ok');
+              expect(firstSpan!.attributes[GEN_AI_INPUT_MESSAGES_ATTRIBUTE].value).toBe(expectedMediaMessages);
+              expect(firstSpan!.attributes[GEN_AI_OPERATION_NAME_ATTRIBUTE].value).toBe('chat');
+              expect(firstSpan!.attributes['sentry.op'].value).toBe('gen_ai.chat');
+              expect(firstSpan!.attributes['sentry.origin'].value).toBe('auto.ai.anthropic');
+              expect(firstSpan!.attributes[GEN_AI_SYSTEM_ATTRIBUTE].value).toBe('anthropic');
+              expect(firstSpan!.attributes[GEN_AI_REQUEST_MODEL_ATTRIBUTE].value).toBe('claude-3-haiku-20240307');
+              expect(firstSpan!.attributes[GEN_AI_INPUT_MESSAGES_ORIGINAL_LENGTH_ATTRIBUTE].value).toBe(2);
+            },
+          })
+          .start()
+          .completed();
+      });
+    },
+  );
 
   createEsmAndCjsTests(
     __dirname,
diff --git a/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/google-genai/instrument-with-truncation.mjs
@@ -0,0 +1,19 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.googleGenAIIntegration({ enableTruncation: true })],
+  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/test.ts b/dev-packages/node-integration-tests/suites/tracing/google-genai/test.ts
@@ -347,7 +347,7 @@ describe('Google GenAI integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'scenario-message-truncation.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit - keeps only last message and crops it', async () => {
         await createRunner()
diff --git a/dev-packages/node-integration-tests/suites/tracing/langchain/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/langchain/instrument-with-truncation.mjs
@@ -0,0 +1,19 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.langChainIntegration({ enableTruncation: true })],
+  beforeSendTransaction: event => {
+    // Filter out mock express server transactions
+    if (event.transaction.includes('/v1/messages') || event.transaction.includes('/v1/embeddings')) {
+      return null;
+    }
+    return event;
+  },
+  streamGenAiSpans: true,
+});
diff --git a/dev-packages/node-integration-tests/suites/tracing/langchain/test.ts b/dev-packages/node-integration-tests/suites/tracing/langchain/test.ts
@@ -199,7 +199,7 @@ describe('LangChain integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'scenario-message-truncation.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit', async () => {
         await createRunner()
diff --git a/dev-packages/node-integration-tests/suites/tracing/langchain/v1/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/langchain/v1/instrument-with-truncation.mjs
@@ -0,0 +1,19 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.langChainIntegration({ enableTruncation: true })],
+  beforeSendTransaction: event => {
+    // Filter out mock express server transactions
+    if (event.transaction.includes('/v1/messages') || event.transaction.includes('/v1/chat/completions')) {
+      return null;
+    }
+    return event;
+  },
+  streamGenAiSpans: true,
+});
diff --git a/dev-packages/node-integration-tests/suites/tracing/langchain/v1/test.ts b/dev-packages/node-integration-tests/suites/tracing/langchain/v1/test.ts
@@ -216,7 +216,7 @@ conditionalTest({ min: 20 })('LangChain integration (v1)', () => {
   createEsmAndCjsTests(
     __dirname,
     'scenario-message-truncation.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit', async () => {
         await createRunner()
diff --git a/dev-packages/node-integration-tests/suites/tracing/openai/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/openai/instrument-with-truncation.mjs
@@ -0,0 +1,18 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.openAIIntegration({ enableTruncation: true })],
+  beforeSendTransaction: event => {
+    if (event.transaction.includes('/openai/')) {
+      return null;
+    }
+    return event;
+  },
+  streamGenAiSpans: true,
+});
diff --git a/dev-packages/node-integration-tests/suites/tracing/openai/test.ts b/dev-packages/node-integration-tests/suites/tracing/openai/test.ts
@@ -1174,7 +1174,7 @@ describe('OpenAI integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'truncation/scenario-message-truncation-completions.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit - keeps only last message and crops it', async () => {
         await createRunner()
@@ -1278,7 +1278,7 @@ describe('OpenAI integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'truncation/scenario-message-truncation-responses.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates string inputs when they exceed byte limit', async () => {
         await createRunner()
@@ -1603,7 +1603,7 @@ describe('OpenAI integration', () => {
     });
   });
 
-  createEsmAndCjsTests(__dirname, 'scenario-vision.mjs', 'instrument-with-pii.mjs', (createRunner, test) => {
+  createEsmAndCjsTests(__dirname, 'scenario-vision.mjs', 'instrument-with-truncation.mjs', (createRunner, test) => {
     test('redacts inline base64 image data in vision requests', async () => {
       await createRunner()
         .ignore('event')
diff --git a/dev-packages/node-integration-tests/suites/tracing/vercelai/instrument-with-truncation.mjs b/dev-packages/node-integration-tests/suites/tracing/vercelai/instrument-with-truncation.mjs
@@ -0,0 +1,12 @@
+import * as Sentry from '@sentry/node';
+import { loggingTransport } from '@sentry-internal/node-integration-tests';
+
+Sentry.init({
+  dsn: 'https://public@dsn.ingest.sentry.io/1337',
+  release: '1.0',
+  tracesSampleRate: 1.0,
+  dataCollection: { genAI: { inputs: true, outputs: true } },
+  transport: loggingTransport,
+  integrations: [Sentry.vercelAIIntegration({ enableTruncation: true })],
+  streamGenAiSpans: true,
+});
diff --git a/dev-packages/node-integration-tests/suites/tracing/vercelai/test.ts b/dev-packages/node-integration-tests/suites/tracing/vercelai/test.ts
@@ -446,7 +446,7 @@ describe('Vercel AI integration', () => {
   createEsmAndCjsTests(
     __dirname,
     'scenario-message-truncation.mjs',
-    'instrument-with-pii.mjs',
+    'instrument-with-truncation.mjs',
     (createRunner, test) => {
       test('truncates messages when they exceed byte limit', async () => {
         await createRunner()
diff --git a/packages/core/src/tracing/ai/utils.ts b/packages/core/src/tracing/ai/utils.ts
@@ -60,11 +60,22 @@ export function resolveAIRecordingOptions<T extends AIRecordingOptions>(options?
 /**
  * Resolves whether truncation should be enabled.
  * If the user explicitly set `enableTruncation`, that value is used.
- * Otherwise, truncation is disabled when span streaming is active.
+ * Otherwise, truncation is disabled when gen_ai spans are streamed — either via full span
+ * streaming (`traceLifecycle: 'stream'`) or by extracting them as v2 envelope items
+ * (`streamGenAiSpans`). Both bypass the transaction payload-size limits that truncation exists
+ * to work around, so the full message data can be retained.
  */
 export function shouldEnableTruncation(enableTruncation: boolean | undefined): boolean {
+  if (enableTruncation !== undefined) {
+    return enableTruncation;
+  }
+
   const client = getClient();
-  return enableTruncation ?? !(client && hasSpanStreamingEnabled(client));
+  if (!client) {
+    return true;
+  }
+
+  return !(hasSpanStreamingEnabled(client) || !!client.getOptions().streamGenAiSpans);
 }
 
 /**
diff --git a/packages/core/src/types/options.ts b/packages/core/src/types/options.ts
@@ -569,6 +569,11 @@ export interface ClientOptions<TO extends BaseTransportOptions = BaseTransportOp
    *
    * This enables streaming gen_ai spans, avoiding payload size limits of usual transactions.
    *
+   * Because the v2 span format is not subject to the transaction payload-size limits that gen_ai message
+   * truncation exists to work around, enabling this option also disables gen_ai input truncation (and the
+   * inline-media redaction that rides along with it) by default. Set `enableTruncation: true` on the
+   * respective AI integration to opt back into truncation.
+   *
    * @default false
    */
   streamGenAiSpans?: boolean;
diff --git a/packages/core/test/lib/tracing/ai/utils.test.ts b/packages/core/test/lib/tracing/ai/utils.test.ts
