diff --git a/codex-rs/core/src/session/prefix_compaction.rs b/codex-rs/core/src/session/prefix_compaction.rs
index dce2267845..ac430f3f77 100644
--- a/codex-rs/core/src/session/prefix_compaction.rs
+++ b/codex-rs/core/src/session/prefix_compaction.rs
@@ -176,7 +176,7 @@ async fn apply_prefix_compact_candidate(
         return Ok(false);
     }
 
-    let compaction_item = TurnItem::ContextCompaction(ContextCompactionItem::new());
+    let compaction_item = TurnItem::ContextCompaction(ContextCompactionItem::new_prefix());
     sess.emit_turn_item_started(turn_context, &compaction_item)
         .await;
 
diff --git a/codex-rs/protocol/src/items.rs b/codex-rs/protocol/src/items.rs
index 601858dd5f..d33255c350 100644
--- a/codex-rs/protocol/src/items.rs
+++ b/codex-rs/protocol/src/items.rs
@@ -130,12 +130,24 @@ pub struct ImageGenerationItem {
 #[derive(Debug, Clone, Deserialize, Serialize, TS, JsonSchema)]
 pub struct ContextCompactionItem {
     pub id: String,
+    #[serde(default, skip_serializing, skip_deserializing)]
+    #[schemars(skip)]
+    #[ts(skip)]
+    pub is_prefix: bool,
 }
 
 impl ContextCompactionItem {
     pub fn new() -> Self {
         Self {
             id: uuid::Uuid::new_v4().to_string(),
+            is_prefix: false,
+        }
+    }
+
+    pub fn new_prefix() -> Self {
+        Self {
+            id: uuid::Uuid::new_v4().to_string(),
+            is_prefix: true,
         }
     }
 
diff --git a/codex-rs/tui/src/app/app_server_adapter.rs b/codex-rs/tui/src/app/app_server_adapter.rs
index f0abb5326e..e35531e272 100644
--- a/codex-rs/tui/src/app/app_server_adapter.rs
+++ b/codex-rs/tui/src/app/app_server_adapter.rs
@@ -894,6 +894,7 @@ fn thread_item_to_core(item: &ThreadItem) -> Option<TurnItem> {
         ThreadItem::ContextCompaction { id } => {
             Some(TurnItem::ContextCompaction(ContextCompactionItem {
                 id: id.clone(),
+                is_prefix: false,
             }))
         }
         ThreadItem::CommandExecution { .. }
diff --git a/codex-rs/tui/src/chatwidget.rs b/codex-rs/tui/src/chatwidget.rs
index 4112ae00b9..825756334f 100644
--- a/codex-rs/tui/src/chatwidget.rs
+++ b/codex-rs/tui/src/chatwidget.rs
@@ -2206,11 +2206,16 @@ impl ChatWidget {
         self.request_redraw();
     }
 
-    fn on_context_compacted(&mut self) {
+    fn on_context_compacted(&mut self, is_prefix: bool) {
         self.flush_answer_stream_with_separator();
         self.handle_stream_finished();
+        let label = if is_prefix {
+            "Context prefix compacted"
+        } else {
+            "Context compacted"
+        };
         self.add_to_history(history_cell::new_info_event(
-            "Context compacted".to_owned(),
+            label.to_owned(),
             /*hint*/ None,
         ));
         self.request_redraw();
@@ -5990,7 +5995,7 @@ impl ChatWidget {
                 self.exit_review_mode_after_item();
             }
             ThreadItem::ContextCompaction { .. } => {
-                self.on_context_compacted();
+                self.on_context_compacted(/*is_prefix*/ false);
             }
             ThreadItem::HookPrompt { .. } => {}
             ThreadItem::CollabAgentToolCall {
@@ -6913,6 +6918,9 @@ impl ChatWidget {
                 if let codex_protocol::items::TurnItem::Plan(plan_item) = &item {
                     self.on_plan_item_completed(plan_item.text.clone());
                 }
+                if let codex_protocol::items::TurnItem::ContextCompaction(item) = &item {
+                    self.on_context_compacted(item.is_prefix);
+                }
                 if let codex_protocol::items::TurnItem::AgentMessage(item) = item {
                     self.on_agent_message_item_completed(item);
                 }