From fc480eccbdbe864812f30724678d8879682d76ca Mon Sep 17 00:00:00 2001
From: Google Team Member <genai-sdk-bot@google.com>
Date: Thu, 18 Jun 2026 06:02:45 -0700
Subject: [PATCH] fix: initialize event ID when creating compaction events

PiperOrigin-RevId: 934305101
---
 .../main/java/com/google/adk/summarizer/LlmEventSummarizer.java | 1 +
 .../java/com/google/adk/summarizer/LlmEventSummarizerTest.java  | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/core/src/main/java/com/google/adk/summarizer/LlmEventSummarizer.java b/core/src/main/java/com/google/adk/summarizer/LlmEventSummarizer.java
index 356175c6b..48808ebdf 100644
--- a/core/src/main/java/com/google/adk/summarizer/LlmEventSummarizer.java
+++ b/core/src/main/java/com/google/adk/summarizer/LlmEventSummarizer.java
@@ -100,6 +100,7 @@ public Maybe<Event> summarizeEvents(List<Event> events) {
                         .map(
                             compaction ->
                                 Event.builder()
+                                    .id(Event.generateEventId())
                                     .author("user")
                                     .actions(EventActions.builder().compaction(compaction).build())
                                     .invocationId(Event.generateEventId())
diff --git a/core/src/test/java/com/google/adk/summarizer/LlmEventSummarizerTest.java b/core/src/test/java/com/google/adk/summarizer/LlmEventSummarizerTest.java
index 1be2a6efe..37371e987 100644
--- a/core/src/test/java/com/google/adk/summarizer/LlmEventSummarizerTest.java
+++ b/core/src/test/java/com/google/adk/summarizer/LlmEventSummarizerTest.java
@@ -100,6 +100,8 @@ public void summarizeEvents_success() {
                 .get(0)
                 .text())
         .hasValue("Summary");
+    assertThat(compactedEvent.id()).isNotNull();
+    assertThat(compactedEvent.id()).isNotEmpty();
     assertThat(compactedEvent.author()).isEqualTo("user");
     assertThat(compactedEvent.actions()).isNotNull();
     assertThat(compactedEvent.actions().compaction()).isPresent();