diff --git a/core/src/main/java/com/google/adk/flows/llmflows/Contents.java b/core/src/main/java/com/google/adk/flows/llmflows/Contents.java
index f45461626..b5f80fbfe 100644
--- a/core/src/main/java/com/google/adk/flows/llmflows/Contents.java
+++ b/core/src/main/java/com/google/adk/flows/llmflows/Contents.java
@@ -406,6 +406,11 @@ private static boolean isEventBelongsToBranch(Optional<String> invocationBranchO
    * @return A new list of events with the appropriate rearrangement.
    */
   private static List<Event> rearrangeEventsForLatestFunctionResponse(List<Event> events) {
+    if (events.size() < 2) {
+      // No need to process, since there is no function_call.
+      return events;
+    }
+
     // TODO: b/412663475 - Handle parallel function calls within the same event. Currently, this
     // throws an error.
     if (events.isEmpty() || Iterables.getLast(events).functionResponses().isEmpty()) {
diff --git a/core/src/test/java/com/google/adk/flows/llmflows/ContentsTest.java b/core/src/test/java/com/google/adk/flows/llmflows/ContentsTest.java
index b5df658ba..b185ad010 100644
--- a/core/src/test/java/com/google/adk/flows/llmflows/ContentsTest.java
+++ b/core/src/test/java/com/google/adk/flows/llmflows/ContentsTest.java
@@ -142,7 +142,9 @@ public void rearrangeLatest_multipleFRsForSameFCAsync_returnsMergedFR() {
   @Test
   public void rearrangeLatest_missingFCEvent_throwsException() {
     Event frEvent = createFunctionResponseEvent("fr1", "tool1", "call1");
-    ImmutableList<Event> events = ImmutableList.of(createUserEvent("u1", "Query"), frEvent);
+    Event frEvent2 = createFunctionResponseEvent("fr2", "tool1", "call1");
+    ImmutableList<Event> events =
+        ImmutableList.of(createUserEvent("u1", "Query"), frEvent, frEvent2);
 
     assertThrows(IllegalStateException.class, () -> runContentsProcessor(events));
   }
@@ -473,10 +475,12 @@ public void processRequest_includeContentsNone_asyncFRAcrossTurns_throwsExceptio
     Event fc1 = createFunctionCallEvent("fc1", "tool1", "call1");
     Event u2 = createUserEvent("u2", "Query 2");
     Event fr1 = createFunctionResponseEvent("fr1", "tool1", "call1"); // FR for fc1
+    Event fr2 = createFunctionResponseEvent("fr2", "tool2", "call1"); // FR for fc2
 
-    ImmutableList<Event> events = ImmutableList.of(u1, fc1, u2, fr1);
+    ImmutableList<Event> events = ImmutableList.of(u1, fc1, u2, fr1, fr2);
 
-    // The current turn starts from u2. fc1 is not in the sublist [u2, fr1], so rearrangement fails.
+    // The current turn starts from u2. fc1 is not in the sublist [u2, fr1, fr2], so rearrangement
+    // fails.
     IllegalStateException e =
         assertThrows(
             IllegalStateException.class,
@@ -486,6 +490,18 @@ public void processRequest_includeContentsNone_asyncFRAcrossTurns_throwsExceptio
         .contains("No function call event found for function response IDs: [call1]");
   }
 
+  @Test
+  public void processRequest_notEnoughEvents_returnsOriginalList() {
+    Event u1 = createUserEvent("u1", "Query 1");
+
+    ImmutableList<Event> events = ImmutableList.of(u1);
+
+    List<Content> result =
+        runContentsProcessorWithIncludeContents(events, LlmAgent.IncludeContents.NONE);
+    assertThat(result).hasSize(1);
+    assertThat(result.get(0)).isEqualTo(u1.content().get());
+  }
+
   @Test
   public void processRequest_includeContentsNone_asyncFRWithinTurn() {
     Event u1 = createUserEvent("u1", "Query 1");