Show model in history (#13034)

packages/cli/src/config/settingsSchema.ts

@@ -483,6 +483,15 @@ const SETTINGS_SCHEMA = {
         description: 'Show citations for generated text in the chat.',
         showInDialog: true,
       },
+      showModelInfoInChat: {
+        type: 'boolean',
+        label: 'Show Model Info In Chat',
+        category: 'UI',
+        requiresRestart: false,
+        default: false,
+        description: 'Show the model name in the chat for each model turn.',
+        showInDialog: true,
+      },
       useFullWidth: {
         type: 'boolean',
         label: 'Use Full Width',

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

@@ -30,6 +30,7 @@ import { getMCPServerStatus } from '@google/gemini-cli-core';
 import { ToolsList } from './views/ToolsList.js';
 import { McpStatus } from './views/McpStatus.js';
 import { ChatList } from './views/ChatList.js';
+import { ModelMessage } from './messages/ModelMessage.js';
 
 interface HistoryItemDisplayProps {
   item: HistoryItem;
@@ -117,6 +118,9 @@ export const HistoryItemDisplay: React.FC<HistoryItemDisplayProps> = ({
       )}
       {itemForDisplay.type === 'model_stats' && <ModelStatsDisplay />}
       {itemForDisplay.type === 'tool_stats' && <ToolStatsDisplay />}
+      {itemForDisplay.type === 'model' && (
+        <ModelMessage model={itemForDisplay.model} />
+      )}
       {itemForDisplay.type === 'quit' && (
         <SessionSummaryDisplay duration={itemForDisplay.duration} />
       )}

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

@@ -0,0 +1,21 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type React from 'react';
+import { Text, Box } from 'ink';
+import { theme } from '../../semantic-colors.js';
+
+interface ModelMessageProps {
+  model: string;
+}
+
+export const ModelMessage: React.FC<ModelMessageProps> = ({ model }) => (
+  <Box marginLeft={3}>
+    <Text color={theme.ui.comment} italic>
+      responding with {model}
+    </Text>
+  </Box>
+);

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

@@ -44,6 +44,7 @@ import type {
   HistoryItemWithoutId,
   HistoryItemToolGroup,
   SlashCommandProcessorResult,
+  HistoryItemModel,
 } from '../types.js';
 import { StreamingState, MessageType, ToolCallStatus } from '../types.js';
 import { isAtCommand, isSlashCommand } from '../utils/commandUtils.js';
@@ -714,6 +715,26 @@ export const useGeminiStream = (
     [addItem, onCancelSubmit, config],
   );
 
+  const handleChatModelEvent = useCallback(
+    (eventValue: string, userMessageTimestamp: number) => {
+      if (!settings?.merged?.ui?.showModelInfoInChat) {
+        return;
+      }
+      if (pendingHistoryItemRef.current) {
+        addItem(pendingHistoryItemRef.current, userMessageTimestamp);
+        setPendingHistoryItem(null);
+      }
+      addItem(
+        {
+          type: 'model',
+          model: eventValue,
+        } as HistoryItemModel,
+        userMessageTimestamp,
+      );
+    },
+    [addItem, pendingHistoryItemRef, setPendingHistoryItem, settings],
+  );
+
   const processGeminiStreamEvents = useCallback(
     async (
       stream: AsyncIterable<GeminiEvent>,
@@ -768,6 +789,9 @@ export const useGeminiStream = (
           case ServerGeminiEventType.Citation:
             handleCitationEvent(event.value, userMessageTimestamp);
             break;
+          case ServerGeminiEventType.ModelInfo:
+            handleChatModelEvent(event.value, userMessageTimestamp);
+            break;
           case ServerGeminiEventType.LoopDetected:
             // handle later because we want to move pending history to history
             // before we add loop detected message to history
@@ -799,9 +823,9 @@ export const useGeminiStream = (
       handleMaxSessionTurnsEvent,
       handleContextWindowWillOverflowEvent,
       handleCitationEvent,
+      handleChatModelEvent,
     ],
   );
-
   const submitQuery = useCallback(
     async (
       query: PartListUnion,

packages/cli/src/ui/types.ts

@@ -151,6 +151,11 @@ export type HistoryItemToolStats = HistoryItemBase & {
   type: 'tool_stats';
 };
 
+export type HistoryItemModel = HistoryItemBase & {
+  type: 'model';
+  model: string;
+};
+
 export type HistoryItemQuit = HistoryItemBase & {
   type: 'quit';
   duration: string;
@@ -250,6 +255,7 @@ export type HistoryItemWithoutId =
   | HistoryItemStats
   | HistoryItemModelStats
   | HistoryItemToolStats
+  | HistoryItemModel
   | HistoryItemQuit
   | HistoryItemCompression
   | HistoryItemExtensionsList