diff --git a/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts b/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts
index cbb90ce72bca..6ba0dcc08cb3 100644
--- a/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts
+++ b/dev-packages/node-integration-tests/suites/tracing/anthropic/test.ts
@@ -8,6 +8,7 @@ import {
   GEN_AI_REQUEST_MODEL_ATTRIBUTE,
   GEN_AI_REQUEST_STREAM_ATTRIBUTE,
   GEN_AI_REQUEST_TEMPERATURE_ATTRIBUTE,
+  GEN_AI_RESPONSE_FINISH_REASONS_ATTRIBUTE,
   GEN_AI_RESPONSE_ID_ATTRIBUTE,
   GEN_AI_RESPONSE_MODEL_ATTRIBUTE,
   GEN_AI_RESPONSE_STREAMING_ATTRIBUTE,
@@ -301,7 +302,9 @@ describe('Anthropic integration', () => {
               expect(span.attributes[GEN_AI_RESPONSE_ID_ATTRIBUTE].value).toBe('msg_stream_1');
             }
 
-            const detailedStreamSpan = requestStreamSpans[0];
+            const detailedStreamSpan = requestStreamSpans.find(
+              span => span.attributes[GEN_AI_RESPONSE_FINISH_REASONS_ATTRIBUTE]?.value === '["end_turn"]',
+            );
             expect(detailedStreamSpan).toBeDefined();
             expect(detailedStreamSpan!.attributes[GEN_AI_SYSTEM_ATTRIBUTE].value).toBe('anthropic');
             expect(detailedStreamSpan!.attributes[GEN_AI_OPERATION_NAME_ATTRIBUTE].value).toBe('chat');
@@ -426,6 +429,7 @@ describe('Anthropic integration', () => {
               expect(span.status).toBe('ok');
               expect(span.attributes['sentry.op'].value).toBe('gen_ai.chat');
               expect(span.attributes[GEN_AI_RESPONSE_STREAMING_ATTRIBUTE].value).toBe(true);
+              expect(span.attributes[GEN_AI_RESPONSE_FINISH_REASONS_ATTRIBUTE].value).toBe('["tool_use"]');
               expect(span.attributes[GEN_AI_REQUEST_AVAILABLE_TOOLS_ATTRIBUTE].value).toBe(EXPECTED_TOOLS_JSON);
               expect(span.attributes[GEN_AI_RESPONSE_TOOL_CALLS_ATTRIBUTE].value).toBe(EXPECTED_TOOL_CALLS_JSON);
             }
diff --git a/packages/core/src/tracing/anthropic-ai/streaming.ts b/packages/core/src/tracing/anthropic-ai/streaming.ts
index d8bc8d3fad2e..68bc9a281001 100644
--- a/packages/core/src/tracing/anthropic-ai/streaming.ts
+++ b/packages/core/src/tracing/anthropic-ai/streaming.ts
@@ -72,12 +72,15 @@ function isErrorEvent(event: AnthropicAiStreamingEvent, span: Span): boolean {
  */
 
 function handleMessageMetadata(event: AnthropicAiStreamingEvent, state: StreamingState): void {
-  // The token counts shown in the usage field of the message_delta event are cumulative.
+  // Cumulative token counts and the final stop reason both arrive on the message_delta event.
   // @see https://docs.anthropic.com/en/docs/build-with-claude/streaming#event-types
-  if (event.type === 'message_delta' && event.usage) {
-    if ('output_tokens' in event.usage && typeof event.usage.output_tokens === 'number') {
+  if (event.type === 'message_delta') {
+    if (event.usage && typeof event.usage.output_tokens === 'number') {
       state.completionTokens = event.usage.output_tokens;
     }
+    if (event.delta?.stop_reason) {
+      state.finishReasons.push(event.delta.stop_reason);
+    }
   }
 
   if (event.message) {
@@ -85,7 +88,6 @@ function handleMessageMetadata(event: AnthropicAiStreamingEvent, state: Streamin
 
     if (message.id) state.responseId = message.id;
     if (message.model) state.responseModel = message.model;
-    if (message.stop_reason) state.finishReasons.push(message.stop_reason);
 
     if (message.usage) {
       if (typeof message.usage.input_tokens === 'number') state.promptTokens = message.usage.input_tokens;