feat(cli): lower compression threshold to 0.2 and update UX

- Change default compression threshold to 200k

- Introduce 'ChatCompressing' event to handle UI loading

- Subtly display context optimization in message footer

- Fix associated snapshot tests

packages/cli/src/ui/AppContainer.tsx

@@ -1061,6 +1061,7 @@ Logging in with Google... Restarting Gemini CLI to continue.
     backgroundShells,
     dismissBackgroundShell,
     retryStatus,
+    isCompressing,
   } = useGeminiStream(
     config.getGeminiClient(),
     historyManager.history,
@@ -1613,6 +1614,7 @@ Logging in with Google... Restarting Gemini CLI to continue.
     streamingState,
     shouldShowFocusHint,
     retryStatus,
+    customWittyPhrases: isCompressing ? ['Optimizing context...'] : undefined,
   });
 
   const handleGlobalKeypress = useCallback(

packages/cli/src/ui/components/HistoryItemDisplay.tsx

@@ -17,7 +17,7 @@ import { ToolGroupMessage } from './messages/ToolGroupMessage.js';
 import { GeminiMessageContent } from './messages/GeminiMessageContent.js';
 import { CompressionMessage } from './messages/CompressionMessage.js';
 import { WarningMessage } from './messages/WarningMessage.js';
-import { Box } from 'ink';
+import { Box, Text } from 'ink';
 import { AboutBox } from './AboutBox.js';
 import { StatsDisplay } from './StatsDisplay.js';
 import { ModelStatsDisplay } from './ModelStatsDisplay.js';
@@ -75,6 +75,14 @@ export const HistoryItemDisplay: React.FC<HistoryItemDisplayProps> = ({
       {itemForDisplay.type === 'user_shell' && (
         <UserShellMessage text={itemForDisplay.text} width={terminalWidth} />
       )}
+      {itemForDisplay.type === 'auto_compression' && (
+        <Box paddingLeft={2} marginTop={0}>
+          <Text dimColor>
+            (Context optimized: {itemForDisplay.compression.originalTokenCount}{' '}
+            → {itemForDisplay.compression.newTokenCount} tokens)
+          </Text>
+        </Box>
+      )}
       {itemForDisplay.type === 'gemini' && (
         <GeminiMessage
           text={itemForDisplay.text}

packages/cli/src/ui/components/__snapshots__/InputPrompt.test.tsx.snap

@@ -77,39 +77,6 @@ exports[`InputPrompt > mouse interaction > should toggle paste expansion on doub
 ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄"
 `;
 
-exports[`InputPrompt > mouse interaction > should toggle paste expansion on double-click 4`] = `
-"▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
- > [Pasted Text: 10 lines]
-▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄"
-`;
-
-exports[`InputPrompt > mouse interaction > should toggle paste expansion on double-click 5`] = `
-"▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
- > [Pasted Text: 10 lines]                                                                                              
-▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄"
-`;
-
-exports[`InputPrompt > mouse interaction > should toggle paste expansion on double-click 6`] = `
-"▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
- > line1                                                                                                                
-   line2                                                                                                                
-   line3                                                                                                                
-   line4                                                                                                                
-   line5                                                                                                                
-   line6                                                                                                                
-   line7                                                                                                                
-   line8                                                                                                                
-   line9                                                                                                                
-   line10                                                                                                               
-▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄"
-`;
-
-exports[`InputPrompt > mouse interaction > should toggle paste expansion on double-click 7`] = `
-"▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
- > [Pasted Text: 10 lines]                                                                                              
-▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄"
-`;
-
 exports[`InputPrompt > snapshots > should not show inverted cursor when shell is focused 1`] = `
 "▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
  >   Type your message or @path/to/file

packages/cli/src/ui/components/messages/GeminiMessage.tsx

@@ -12,7 +12,6 @@ import { theme } from '../../semantic-colors.js';
 import { SCREEN_READER_MODEL_PREFIX } from '../../textConstants.js';
 import { useUIState } from '../../contexts/UIStateContext.js';
 import { useAlternateBuffer } from '../../hooks/useAlternateBuffer.js';
-
 interface GeminiMessageProps {
   text: string;
   isPending: boolean;

packages/cli/src/ui/hooks/useGeminiStream.ts

@@ -53,6 +53,7 @@ import { type Part, type PartListUnion, FinishReason } from '@google/genai';
 import type {
   HistoryItem,
   HistoryItemThinking,
+  HistoryItemAutoCompression,
   HistoryItemWithoutId,
   HistoryItemToolGroup,
   IndividualToolCallDisplay,
@@ -203,6 +204,8 @@ export const useGeminiStream = (
   const [pendingHistoryItem, pendingHistoryItemRef, setPendingHistoryItem] =
     useStateAndRef<HistoryItemWithoutId | null>(null);
 
+  const [isCompressing, setIsCompressing] = useState<boolean>(false);
+
   const [lastGeminiActivityTime, setLastGeminiActivityTime] =
     useState<number>(0);
   const [pushedToolCallIds, pushedToolCallIdsRef, setPushedToolCallIds] =
@@ -765,7 +768,10 @@ export const useGeminiStream = (
         if (pendingHistoryItemRef.current) {
           addItem(pendingHistoryItemRef.current, userMessageTimestamp);
         }
-        setPendingHistoryItem({ type: 'gemini', text: '' });
+        setPendingHistoryItem({
+          type: 'gemini',
+          text: '',
+        });
         newGeminiMessageBuffer = eventValue;
       }
       // Split large messages for better rendering performance. Ideally,
@@ -773,11 +779,23 @@ export const useGeminiStream = (
       const splitPoint = findLastSafeSplitPoint(newGeminiMessageBuffer);
       if (splitPoint === newGeminiMessageBuffer.length) {
         // Update the existing message with accumulated content
-        setPendingHistoryItem((item) => ({
+        setPendingHistoryItem((item) => {
-          // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
+          if (!item) return null;
-          type: item?.type as 'gemini' | 'gemini_content',
+          if (item.type === 'gemini') {
-          text: newGeminiMessageBuffer,
+            return {
-        }));
+              ...item,
+              type: 'gemini',
+              text: newGeminiMessageBuffer,
+            };
+          } else if (item.type === 'gemini_content') {
+            return {
+              ...item,
+              type: 'gemini_content',
+              text: newGeminiMessageBuffer,
+            };
+          }
+          return item;
+        });
       } else {
         // This indicates that we need to split up this Gemini Message.
         // Splitting a message is primarily a performance consideration. There is a
@@ -799,7 +817,10 @@ export const useGeminiStream = (
           },
           userMessageTimestamp,
         );
-        setPendingHistoryItem({ type: 'gemini_content', text: afterText });
+        setPendingHistoryItem({
+          type: 'gemini_content',
+          text: afterText,
+        });
         newGeminiMessageBuffer = afterText;
       }
       return newGeminiMessageBuffer;
@@ -956,14 +977,16 @@ export const useGeminiStream = (
         addItem(pendingHistoryItemRef.current, userMessageTimestamp);
         setPendingHistoryItem(null);
       }
-      return addItem({
+
-        type: 'info',
+      if (eventValue) {
-        text:
+        addItem(
-          `IMPORTANT: This conversation exceeded the compress threshold. ` +
+          {
-          `A compressed context will be sent for future messages (compressed from: ` +
+            type: 'auto_compression',
-          `${eventValue?.originalTokenCount ?? 'unknown'} to ` +
+            compression: eventValue,
-          `${eventValue?.newTokenCount ?? 'unknown'} tokens).`,
+          } as HistoryItemAutoCompression,
-      });
+          userMessageTimestamp,
+        );
+      }
     },
     [addItem, pendingHistoryItemRef, setPendingHistoryItem],
   );
@@ -1095,6 +1118,10 @@ export const useGeminiStream = (
       let geminiMessageBuffer = '';
       const toolCallRequests: ToolCallRequestInfo[] = [];
       for await (const event of stream) {
+        if (event.type !== ServerGeminiEventType.ChatCompressing) {
+          setIsCompressing(false);
+        }
+
         if (
           event.type !== ServerGeminiEventType.Thought &&
           thoughtRef.current !== null
@@ -1140,7 +1167,11 @@ export const useGeminiStream = (
               event.value.contextCleared,
             );
             break;
+          case ServerGeminiEventType.ChatCompressing:
+            setIsCompressing(true);
+            break;
           case ServerGeminiEventType.ChatCompressed:
+            setIsCompressing(false);
             handleChatCompressionEvent(event.value, userMessageTimestamp);
             break;
           case ServerGeminiEventType.ToolCallConfirmation:
@@ -1683,6 +1714,7 @@ export const useGeminiStream = (
 
   return {
     streamingState,
+    isCompressing,
     submitQuery,
     initError,
     pendingHistoryItems,

packages/cli/src/ui/types.ts

@@ -6,6 +6,7 @@
 
 import {
   type CompressionStatus,
+  type ChatCompressionInfo,
   type GeminiCLIExtension,
   type MCPServerConfig,
   type ThoughtSummary,
@@ -248,6 +249,11 @@ export type HistoryItemThinking = HistoryItemBase & {
   thought: ThoughtSummary;
 };
 
+export type HistoryItemAutoCompression = HistoryItemBase & {
+  type: 'auto_compression';
+  compression: ChatCompressionInfo;
+};
+
 export type HistoryItemChatList = HistoryItemBase & {
   type: 'chat_list';
   chats: ChatDetail[];
@@ -372,6 +378,7 @@ export type HistoryItemWithoutId =
   | HistoryItemMcpStatus
   | HistoryItemChatList
   | HistoryItemThinking
+  | HistoryItemAutoCompression
   | HistoryItemHooksList;
 
 export type HistoryItem = HistoryItemWithoutId & { id: number };

packages/core/src/core/client.test.ts

@@ -1077,6 +1077,7 @@ ${JSON.stringify(
         new AbortController().signal,
         'test-prompt-id',
       );
+      await stream.next(); // Trigger ChatCompressing
       await stream.next(); // Trigger the generator
 
       expect(countTokensSpy).toHaveBeenCalledWith(
@@ -1924,8 +1925,10 @@ ${JSON.stringify(
 
       // Assert
       expect(events).toEqual([
+        { type: GeminiEventType.ChatCompressing },
         { type: GeminiEventType.ModelInfo, value: 'default-routed-model' },
         { type: GeminiEventType.InvalidStream },
+        { type: GeminiEventType.ChatCompressing },
         { type: GeminiEventType.Content, value: 'Continued content' },
       ]);
 
@@ -1980,6 +1983,7 @@ ${JSON.stringify(
 
       // Assert
       expect(events).toEqual([
+        { type: GeminiEventType.ChatCompressing },
         { type: GeminiEventType.ModelInfo, value: 'default-routed-model' },
         { type: GeminiEventType.InvalidStream },
       ]);
@@ -2017,8 +2021,8 @@ ${JSON.stringify(
       const events = await fromAsync(stream);
 
       // Assert
-      // We expect 3 events (model_info + original + 1 retry)
+      // We expect 5 events (chat_compressing + model_info + original + 1 retry chat_compressing + 1 retry model_info)
-      expect(events.length).toBe(3);
+      expect(events.length).toBe(5);
       expect(
         events
           .filter((e) => e.type === GeminiEventType.ModelInfo)

packages/core/src/core/client.ts

@@ -571,6 +571,7 @@ export class GeminiClient {
     // Check for context window overflow
     const modelForLimitCheck = this._getActiveModelForCurrentTurn();
 
+    yield { type: GeminiEventType.ChatCompressing };
     const compressed = await this.tryCompressChat(prompt_id, false);
 
     if (compressed.compressionStatus === CompressionStatus.COMPRESSED) {

packages/core/src/core/turn.ts

@@ -68,6 +68,7 @@ export enum GeminiEventType {
   ModelInfo = 'model_info',
   AgentExecutionStopped = 'agent_execution_stopped',
   AgentExecutionBlocked = 'agent_execution_blocked',
+  ChatCompressing = 'chat_compressing',
 }
 
 export type ServerGeminiRetryEvent = {
@@ -192,6 +193,10 @@ export type ServerGeminiChatCompressedEvent = {
   value: ChatCompressionInfo | null;
 };
 
+export type ServerGeminiChatCompressingEvent = {
+  type: GeminiEventType.ChatCompressing;
+};
+
 export type ServerGeminiMaxSessionTurnsEvent = {
   type: GeminiEventType.MaxSessionTurns;
 };
@@ -213,6 +218,7 @@ export type ServerGeminiCitationEvent = {
 // The original union type, now composed of the individual types
 export type ServerGeminiStreamEvent =
   | ServerGeminiChatCompressedEvent
+  | ServerGeminiChatCompressingEvent
   | ServerGeminiCitationEvent
   | ServerGeminiContentEvent
   | ServerGeminiErrorEvent

packages/core/src/services/chatCompressionService.ts

@@ -36,7 +36,7 @@ import { PreCompressTrigger } from '../hooks/types.js';
  * Default threshold for compression token count as a fraction of the model's
  * token limit. If the chat history exceeds this threshold, it will be compressed.
  */
-export const DEFAULT_COMPRESSION_TOKEN_THRESHOLD = 0.5;
+export const DEFAULT_COMPRESSION_TOKEN_THRESHOLD = 0.2;
 
 /**
  * The fraction of the latest chat history to keep. A value of 0.3