feat(mcp): add live MCP tool progress bar for long running MCP tool calls (Issue #16934)

packages/cli/src/ui/commands/mcpCommand.test.ts

@@ -14,9 +14,8 @@ import {
   getMCPDiscoveryState,
   DiscoveredMCPTool,
   type MessageBus,
+  type CallableToolWithProgress,
 } from '@google/gemini-cli-core';
-
-import type { CallableTool } from '@google/genai';
 import { MessageType } from '../types.js';
 
 vi.mock('@google/gemini-cli-core', async (importOriginal) => {
@@ -53,7 +52,7 @@ const createMockMCPTool = (
     {
       callTool: vi.fn(),
       tool: vi.fn(),
-    } as unknown as CallableTool,
+    } as unknown as CallableToolWithProgress,
     serverName,
     name,
     description || 'Mock tool description',

packages/cli/src/ui/components/messages/ToolMessage.test.tsx

@@ -6,7 +6,7 @@
 
 import type React from 'react';
 import { ToolMessage, type ToolMessageProps } from './ToolMessage.js';
-import { describe, it, expect, vi } from 'vitest';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
 import { StreamingState } from '../../types.js';
 import { Text } from 'ink';
 import { type AnsiOutput, CoreToolCallStatus } from '@google/gemini-cli-core';
@@ -299,6 +299,18 @@ describe('<ToolMessage />', () => {
     expect(lowEmphasisFrame()).toMatchSnapshot();
   });
 
+  it('renders MCPProgressIndicator when executing with progress', () => {
+    const { lastFrame } = renderWithContext(
+      <ToolMessage
+        {...baseProps}
+        status={CoreToolCallStatus.Executing}
+        mcpProgress={{ progress: 50, total: 100, message: 'Processing...' }}
+      />,
+      StreamingState.Responding,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
   it('renders AnsiOutputText for AnsiOutput results', () => {
     const ansiResult: AnsiOutput = [
       [

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

@@ -13,14 +13,15 @@ import {
   ToolStatusIndicator,
   ToolInfo,
   TrailingIndicator,
+  MCPProgressIndicator,
   type TextEmphasis,
   STATUS_INDICATOR_WIDTH,
   isThisShellFocusable as checkIsShellFocusable,
   isThisShellFocused as checkIsShellFocused,
   useFocusHint,
   FocusHint,
 } from './ToolShared.js';
-import { type Config } from '@google/gemini-cli-core';
+import { type Config, CoreToolCallStatus } from '@google/gemini-cli-core';
 import { ShellInputPrompt } from '../ShellInputPrompt.js';
 
 export type { TextEmphasis };
@@ -55,6 +56,7 @@ export const ToolMessage: React.FC<ToolMessageProps> = ({
   embeddedShellFocused,
   ptyId,
   config,
+  mcpProgress,
 }) => {
   const isThisShellFocused = checkIsShellFocused(
     name,
@@ -108,6 +110,17 @@ export const ToolMessage: React.FC<ToolMessageProps> = ({
         paddingX={1}
         flexDirection="column"
       >
+        {status === CoreToolCallStatus.Executing && mcpProgress && (
+          <MCPProgressIndicator
+            progress={mcpProgress.progress}
+            total={mcpProgress.total}
+            message={mcpProgress.message}
+            barWidth={Math.max(
+              10,
+              Math.min(Math.floor(terminalWidth * 0.4), 40),
+            )}
+          />
+        )}
         <ToolResultDisplay
           resultDisplay={resultDisplay}
           availableTerminalHeight={availableTerminalHeight}

packages/cli/src/ui/components/messages/ToolShared.test.tsx

@@ -0,0 +1,58 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { render } from '../../../test-utils/render.js';
+import { MCPProgressIndicator } from './ToolShared.js';
+import { describe, it, expect } from 'vitest';
+
+describe('MCPProgressIndicator', () => {
+  it('renders determinate progress bar at 50%', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator progress={50} total={100} barWidth={20} />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
+  it('renders fully complete progress bar', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator progress={100} total={100} barWidth={20} />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
+  it('renders indeterminate progress without total', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator progress={5} barWidth={20} />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
+  it('renders progress message when provided', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator
+        progress={50}
+        total={100}
+        message="Downloading..."
+        barWidth={20}
+      />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
+  it('scales bar width correctly', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator progress={50} total={100} barWidth={40} />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+
+  it('clamps progress exceeding total', () => {
+    const { lastFrame } = render(
+      <MCPProgressIndicator progress={150} total={100} barWidth={20} />,
+    );
+    expect(lastFrame()).toMatchSnapshot();
+  });
+});

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

@@ -233,3 +233,55 @@ export const TrailingIndicator: React.FC = () => (
     ←
   </Text>
 );
+
+export interface MCPProgressIndicatorProps {
+  progress: number;
+  total?: number;
+  message?: string;
+  barWidth: number;
+}
+
+/**
+ * Values are clamped to prevent crashes from negative repeat counts
+ * when progress > total (which can happen with misbehaving MCP servers).
+ */
+export const MCPProgressIndicator: React.FC<MCPProgressIndicatorProps> = ({
+  progress,
+  total,
+  message,
+  barWidth,
+}) => {
+  const percentage =
+    total && total > 0
+      ? Math.min(100, Math.round((progress / total) * 100))
+      : null;
+
+  let rawFilled: number;
+  if (total && total > 0) {
+    rawFilled = Math.round((progress / total) * barWidth);
+  } else {
+    rawFilled = Math.floor(progress) % (barWidth + 1);
+  }
+
+  const filled = Math.max(
+    0,
+    Math.min(Number.isFinite(rawFilled) ? rawFilled : 0, barWidth),
+  );
+  const empty = Math.max(0, barWidth - filled);
+  const progressBar = '\u2588'.repeat(filled) + '\u2591'.repeat(empty);
+
+  return (
+    <Box flexDirection="column" marginTop={1}>
+      <Box>
+        <Text color={theme.text.accent}>
+          {progressBar} {percentage !== null ? `${percentage}%` : `${progress}`}
+        </Text>
+      </Box>
+      {message && (
+        <Text color={theme.text.secondary} wrap="truncate">
+          {message}
+        </Text>
+      )}
+    </Box>
+  );
+};

packages/cli/src/ui/components/messages/__snapshots__/ToolMessage.test.tsx.snap

@@ -81,6 +81,16 @@ exports[`<ToolMessage /> > renders DiffRenderer for diff results 1`] = `
 │ 1 + new                                                                      │"
 `;
 
+exports[`<ToolMessage /> > renders MCPProgressIndicator when executing with progress 1`] = `
+"╭──────────────────────────────────────────────────────────────────────────────╮
+│ MockRespondingSpinnertest-tool A tool for testing                            │
+│                                                                              │
+│                                                                              │
+│ ████████████████░░░░░░░░░░░░░░░░ 50%                                         │
+│ Processing...                                                                │
+│ Test result                                                                  │"
+`;
+
 exports[`<ToolMessage /> > renders basic tool information 1`] = `
 "╭──────────────────────────────────────────────────────────────────────────────╮
 │ ✓  test-tool A tool for testing                                              │

packages/cli/src/ui/components/messages/__snapshots__/ToolShared.test.tsx.snap

@@ -0,0 +1,32 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`MCPProgressIndicator > clamps progress exceeding total 1`] = `
+"
+████████████████████ 100%"
+`;
+
+exports[`MCPProgressIndicator > renders determinate progress bar at 50% 1`] = `
+"
+██████████░░░░░░░░░░ 50%"
+`;
+
+exports[`MCPProgressIndicator > renders fully complete progress bar 1`] = `
+"
+████████████████████ 100%"
+`;
+
+exports[`MCPProgressIndicator > renders indeterminate progress without total 1`] = `
+"
+█████░░░░░░░░░░░░░░░ 5"
+`;
+
+exports[`MCPProgressIndicator > renders progress message when provided 1`] = `
+"
+██████████░░░░░░░░░░ 50%
+Downloading..."
+`;
+
+exports[`MCPProgressIndicator > scales bar width correctly 1`] = `
+"
+████████████████████░░░░░░░░░░░░░░░░░░░░ 50%"
+`;

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

@@ -11,6 +11,7 @@ import {
   debugLogger,
   CoreToolCallStatus,
 } from '@google/gemini-cli-core';
+import type { Progress } from '@modelcontextprotocol/sdk/types.js';
 import {
   type HistoryItemToolGroup,
   type IndividualToolCallDisplay,
@@ -54,6 +55,7 @@ export function mapToDisplay(
     let outputFile: string | undefined = undefined;
     let ptyId: number | undefined = undefined;
     let correlationId: string | undefined = undefined;
+    let mcpProgress: Progress | undefined = undefined;
 
     switch (call.status) {
       case CoreToolCallStatus.Success:
@@ -72,6 +74,7 @@ export function mapToDisplay(
       case CoreToolCallStatus.Executing:
         resultDisplay = call.liveOutput;
         ptyId = call.pid;
+        mcpProgress = call.mcpProgress;
         break;
       case CoreToolCallStatus.Scheduled:
       case CoreToolCallStatus.Validating:
@@ -96,6 +99,7 @@ export function mapToDisplay(
       ptyId,
       correlationId,
       approvalMode: call.approvalMode,
+      mcpProgress,
     };
   });
 

packages/cli/src/ui/types.ts

@@ -18,6 +18,7 @@ import {
   CoreToolCallStatus,
   checkExhaustive,
 } from '@google/gemini-cli-core';
+import type { Progress } from '@modelcontextprotocol/sdk/types.js';
 import type { PartListUnion } from '@google/genai';
 import { type ReactNode } from 'react';
 
@@ -108,6 +109,7 @@ export interface IndividualToolCallDisplay {
   outputFile?: string;
   correlationId?: string;
   approvalMode?: ApprovalMode;
+  mcpProgress?: Progress;
 }
 
 export interface CompressionProps {

packages/core/src/agents/local-executor.test.ts

@@ -21,6 +21,7 @@ import {
   DiscoveredMCPTool,
   MCP_QUALIFIED_NAME_SEPARATOR,
 } from '../tools/mcp-tool.js';
+import type { CallableToolWithProgress } from '../tools/mcp-client.js';
 import { LSTool } from '../tools/ls.js';
 import { LS_TOOL_NAME, READ_FILE_TOOL_NAME } from '../tools/tool-names.js';
 import {
@@ -35,7 +36,6 @@ import {
   type Content,
   type PartListUnion,
   type Tool,
-  type CallableTool,
 } from '@google/genai';
 import type { Config } from '../config/config.js';
 import { MockTool } from '../test-utils/mock-tool.js';
@@ -508,7 +508,7 @@ describe('LocalAgentExecutor', () => {
       const mockMcpTool = {
         tool: vi.fn(),
         callTool: vi.fn(),
-      } as unknown as CallableTool;
+      } as unknown as CallableToolWithProgress;
 
       const mcpTool = new DiscoveredMCPTool(
         mockMcpTool,

packages/core/src/core/coreToolScheduler.test.ts

@@ -6,7 +6,7 @@
 
 import { describe, it, expect, vi } from 'vitest';
 import type { Mock } from 'vitest';
-import type { CallableTool } from '@google/genai';
+import type { CallableToolWithProgress } from '../tools/mcp-client.js';
 import { CoreToolScheduler } from './coreToolScheduler.js';
 import {
   type ToolCall,
@@ -1934,7 +1934,7 @@ describe('CoreToolScheduler Sequential Execution', () => {
     const serverName = 'test-server';
     const toolName = 'test-tool';
     const mcpTool = new DiscoveredMCPTool(
-      mockMcpTool as unknown as CallableTool,
+      mockMcpTool as unknown as CallableToolWithProgress,
       serverName,
       toolName,
       'description',

packages/core/src/core/prompts.test.ts

@@ -25,7 +25,7 @@ import {
 } from '../config/models.js';
 import { ApprovalMode } from '../policy/types.js';
 import { DiscoveredMCPTool } from '../tools/mcp-tool.js';
-import type { CallableTool } from '@google/genai';
+import type { CallableToolWithProgress } from '../tools/mcp-client.js';
 import type { MessageBus } from '../confirmation-bus/message-bus.js';
 
 // Mock tool names if they are dynamically generated or complex
@@ -442,7 +442,7 @@ describe('Core System Prompt (prompts.ts)', () => {
       vi.mocked(mockConfig.getApprovalMode).mockReturnValue(ApprovalMode.PLAN);
 
       const readOnlyMcpTool = new DiscoveredMCPTool(
-        {} as CallableTool,
+        {} as CallableToolWithProgress,
         'readonly-server',
         'read_static_value',
         'A read-only tool',
@@ -453,7 +453,7 @@ describe('Core System Prompt (prompts.ts)', () => {
       );
 
       const nonReadOnlyMcpTool = new DiscoveredMCPTool(
-        {} as CallableTool,
+        {} as CallableToolWithProgress,
         'nonreadonly-server',
         'non_read_static_value',
         'A non-read-only tool',