fix(core): reduce intrusive MCP errors and deduplicate diagnostics (#20232)

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

@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-import { vi, describe, it, expect, beforeEach } from 'vitest';
+import { vi, describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { mcpCommand } from './mcpCommand.js';
 import { createMockCommandContext } from '../../test-utils/mockCommandContext.js';
 import {
@@ -77,6 +77,8 @@ describe('mcpCommand', () => {
     getGeminiClient: ReturnType<typeof vi.fn>;
     getMcpClientManager: ReturnType<typeof vi.fn>;
     getResourceRegistry: ReturnType<typeof vi.fn>;
+    setUserInteractedWithMcp: ReturnType<typeof vi.fn>;
+    getLastMcpError: ReturnType<typeof vi.fn>;
   };
 
   beforeEach(() => {
@@ -104,12 +106,15 @@ describe('mcpCommand', () => {
       }),
       getGeminiClient: vi.fn(),
       getMcpClientManager: vi.fn().mockImplementation(() => ({
-        getBlockedMcpServers: vi.fn(),
-        getMcpServers: vi.fn(),
+        getBlockedMcpServers: vi.fn().mockReturnValue([]),
+        getMcpServers: vi.fn().mockReturnValue({}),
+        getLastError: vi.fn().mockReturnValue(undefined),
       })),
       getResourceRegistry: vi.fn().mockReturnValue({
         getAllResources: vi.fn().mockReturnValue([]),
       }),
+      setUserInteractedWithMcp: vi.fn(),
+      getLastMcpError: vi.fn().mockReturnValue(undefined),
     };
 
     mockContext = createMockCommandContext({
@@ -119,6 +124,10 @@ describe('mcpCommand', () => {
     });
   });
 
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
   describe('basic functionality', () => {
     it('should show an error if config is not available', async () => {
       const contextWithoutConfig = createMockCommandContext({
@@ -161,6 +170,7 @@ describe('mcpCommand', () => {
       mockConfig.getMcpClientManager = vi.fn().mockReturnValue({
         getMcpServers: vi.fn().mockReturnValue(mockMcpServers),
         getBlockedMcpServers: vi.fn().mockReturnValue([]),
+        getLastError: vi.fn().mockReturnValue(undefined),
       });
     });
 

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

@@ -52,6 +52,8 @@ const authCommand: SlashCommand = {
       };
     }
 
+    config.setUserInteractedWithMcp();
+
     const mcpServers = config.getMcpClientManager()?.getMcpServers() ?? {};
 
     if (!serverName) {
@@ -184,6 +186,8 @@ const listAction = async (
     };
   }
 
+  config.setUserInteractedWithMcp();
+
   const toolRegistry = config.getToolRegistry();
   if (!toolRegistry) {
     return {
@@ -250,6 +254,13 @@ const listAction = async (
     enablementState[serverName] =
       await enablementManager.getDisplayState(serverName);
   }
+  const errors: Record<string, string> = {};
+  for (const serverName of serverNames) {
+    const error = config.getMcpClientManager()?.getLastError(serverName);
+    if (error) {
+      errors[serverName] = error;
+    }
+  }
 
   const mcpStatusItem: HistoryItemMcpStatus = {
     type: MessageType.MCP_STATUS,
@@ -274,16 +285,19 @@ const listAction = async (
     })),
     authStatus,
     enablementState,
-    blockedServers: blockedMcpServers,
+    errors,
+    blockedServers: blockedMcpServers.map((s) => ({
+      name: s.name,
+      extensionName: s.extensionName,
+    })),
     discoveryInProgress,
     connectingServers,
-    showDescriptions,
-    showSchema,
+    showDescriptions: Boolean(showDescriptions),
+    showSchema: Boolean(showSchema),
   };
 
   context.ui.addItem(mcpStatusItem);
 };
-
 const listCommand: SlashCommand = {
   name: 'list',
   altNames: ['ls', 'nodesc', 'nodescription'],
@@ -372,6 +386,8 @@ async function handleEnableDisable(
     };
   }
 
+  config.setUserInteractedWithMcp();
+
   const parts = args.trim().split(/\s+/);
   const isSession = parts.includes('--session');
   const serverName = parts.filter((p) => p !== '--session')[0];

packages/cli/src/ui/components/views/McpStatus.test.tsx

@@ -47,6 +47,7 @@ describe('McpStatus', () => {
         isPersistentDisabled: false,
       },
     },
+    errors: {},
     discoveryInProgress: false,
     connectingServers: [],
     showDescriptions: true,
@@ -208,6 +209,18 @@ describe('McpStatus', () => {
     unmount();
   });
 
+  it('renders correctly with a server error', async () => {
+    const { lastFrame, unmount, waitUntilReady } = render(
+      <McpStatus
+        {...baseProps}
+        errors={{ 'server-1': 'Failed to connect to server' }}
+      />,
+    );
+    await waitUntilReady();
+    expect(lastFrame()).toMatchSnapshot();
+    unmount();
+  });
+
   it('truncates resources when exceeding limit', async () => {
     const manyResources = Array.from({ length: 25 }, (_, i) => ({
       serverName: 'server-1',

packages/cli/src/ui/components/views/McpStatus.tsx

@@ -26,6 +26,7 @@ interface McpStatusProps {
   serverStatus: (serverName: string) => MCPServerStatus;
   authStatus: HistoryItemMcpStatus['authStatus'];
   enablementState: HistoryItemMcpStatus['enablementState'];
+  errors: Record<string, string>;
   discoveryInProgress: boolean;
   connectingServers: string[];
   showDescriptions: boolean;
@@ -41,6 +42,7 @@ export const McpStatus: React.FC<McpStatusProps> = ({
   serverStatus,
   authStatus,
   enablementState,
+  errors,
   discoveryInProgress,
   connectingServers,
   showDescriptions,
@@ -195,6 +197,14 @@ export const McpStatus: React.FC<McpStatusProps> = ({
               <Text> ({toolCount} tools cached)</Text>
             )}
 
+            {errors[serverName] && (
+              <Box marginLeft={2}>
+                <Text color={theme.status.error}>
+                  Error: {errors[serverName]}
+                </Text>
+              </Box>
+            )}
+
             {showDescriptions && server?.description && (
               <Text color={theme.text.secondary}>
                 {server.description.trim()}

packages/cli/src/ui/components/views/__snapshots__/McpStatus.test.tsx.snap

@@ -60,6 +60,18 @@ A test server
 "
 `;
 
+exports[`McpStatus > renders correctly with a server error 1`] = `
+"Configured MCP servers:
+
+🟢 server-1 - Ready (1 tool)
+  Error: Failed to connect to server
+A test server
+  Tools:
+  - tool-1
+    A test tool
+"
+`;
+
 exports[`McpStatus > renders correctly with authenticated OAuth status 1`] = `
 "Configured MCP servers:
 

packages/cli/src/ui/types.ts

@@ -340,6 +340,7 @@ export type HistoryItemMcpStatus = HistoryItemBase & {
       isPersistentDisabled: boolean;
     }
   >;
+  errors: Record<string, string>;
   blockedServers: Array<{ name: string; extensionName: string }>;
   discoveryInProgress: boolean;
   connectingServers: string[];