Fix string input truncation

Author: nicohrubec

dev-packages/node-integration-tests/suites/tracing/openai/test.ts

@@ -439,7 +439,7 @@ describe('OpenAI integration', () => {
     'scenario-message-truncation-responses.mjs',
     'instrument-with-pii.mjs',
     (createRunner, test) => {
-      test('should truncate input strings that exceed byte limit', async () => {
+      test('truncates string inputs when they exceed byte limit', async () => {
         await createRunner()
           .ignore('event')
           .expect({
@@ -453,7 +453,7 @@ describe('OpenAI integration', () => {
                     'sentry.origin': 'auto.ai.openai',
                     'gen_ai.system': 'openai',
                     'gen_ai.request.model': 'gpt-3.5-turbo',
-                    // Message should be present but truncated to include only As
+                    // Messages should be present and should include truncated string input (contains only As)
                     'gen_ai.request.messages': expect.stringMatching(/^A+$/),
                   }),
                   description: 'responses gpt-3.5-turbo',

packages/core/src/utils/ai/messageTruncation.ts

@@ -294,3 +294,13 @@ export function truncateMessagesByBytes(messages: unknown[], maxBytes: number):
 export function truncateGenAiMessages(messages: unknown[]): unknown[] {
   return truncateMessagesByBytes(messages, DEFAULT_GEN_AI_MESSAGES_BYTE_LIMIT);
 }
+
+/**
+ * Truncate GenAI string input using the default byte limit.
+ *
+ * @param input - The string to truncate
+ * @returns Truncated string
+ */
+export function truncateGenAiStringInput(input: string): string {
+  return truncateTextByBytes(input, DEFAULT_GEN_AI_MESSAGES_BYTE_LIMIT);
+}

packages/core/src/utils/ai/utils.ts

@@ -7,7 +7,7 @@ import {
   GEN_AI_USAGE_OUTPUT_TOKENS_ATTRIBUTE,
   GEN_AI_USAGE_TOTAL_TOKENS_ATTRIBUTE,
 } from './gen-ai-attributes';
-import { truncateGenAiMessages } from './messageTruncation';
+import { truncateGenAiMessages, truncateGenAiStringInput } from './messageTruncation';
 /**
  * Maps AI method paths to Sentry operation name
  */
@@ -95,7 +95,7 @@ export function setTokenUsageAttributes(
 export function getTruncatedJsonString<T>(value: T | T[]): string {
   if (typeof value === 'string') {
     // Some values are already JSON strings, so we don't need to duplicate the JSON parsing
-    return value;
+    return truncateGenAiStringInput(value);
   }
   if (Array.isArray(value)) {
     // truncateGenAiMessages returns an array of strings, so we need to stringify it