feat: warn users when too many MCP tools are enabled (#10772)

* feat: warn users when too many MCP tools are enabled - Add WarningRow component for displaying generic warnings with icon, title, message, and optional docs link - Add TooManyToolsWarning component that shows when users have more than 40 MCP tools enabled - Add MAX_MCP_TOOLS_THRESHOLD constant (40) - Add i18n translations for the warning message - Integrate warning into ChatView to display after task header - Add comprehensive tests for both components Closes ROO-542 * Moves constant to the right place * Move it to the backend * i18n * Add actionlink that takes you to MCP settings in this case * Add to MCP settings too * Bump max tools up to 60 since github itself has 50+ * DRY * Fix test --------- Co-authored-by: Roo Code <roomote@roocode.com> Co-authored-by: Bruno Bergher <bruno@roocode.com> Co-authored-by: Matt Rubens <mrubens@users.noreply.github.com>
2026-10-08 03:07:53 +00:00 · 2026-01-18 09:22:09 -05:00 · 2026-01-18 09:22:09 -05:00 · a148862a06
commit a148862a06
parent 719e6cb35b
29 changed files with 906 additions and 2 deletions
--- a/packages/types/src/mcp.ts
+++ b/packages/types/src/mcp.ts
@ -1,5 +1,11 @@
 import { z } from "zod"

+/**
+ * Maximum number of MCP tools that can be enabled before showing a warning.
+ * LLMs tend to perform poorly when given too many tools to choose from.
+ */
+export const MAX_MCP_TOOLS_THRESHOLD = 60
+
 /**
 * McpServerUse
 */
@ -128,3 +134,53 @@ export type McpErrorEntry = {
 	timestamp: number
 	level: "error" | "warn" | "info"
 }
+
+/**
+ * Result of counting enabled MCP tools across servers.
+ */
+export interface EnabledMcpToolsCount {
+	/** Number of enabled and connected MCP servers */
+	enabledServerCount: number
+	/** Total number of enabled tools across all enabled servers */
+	enabledToolCount: number
+}
+
+/**
+ * Count the number of enabled MCP tools across all enabled and connected servers.
+ * This is a pure function that can be used in both backend and frontend contexts.
+ *
+ * @param servers - Array of MCP server objects
+ * @returns Object with enabledToolCount and enabledServerCount
+ *
+ * @example
+ * const { enabledToolCount, enabledServerCount } = countEnabledMcpTools(mcpServers)
+ * if (enabledToolCount > MAX_MCP_TOOLS_THRESHOLD) {
+ *   // Show warning
+ * }
+ */
+export function countEnabledMcpTools(servers: McpServer[]): EnabledMcpToolsCount {
+	let serverCount = 0
+	let toolCount = 0
+
+	for (const server of servers) {
+		// Skip disabled servers
+		if (server.disabled) continue
+
+		// Skip servers that are not connected
+		if (server.status !== "connected") continue
+
+		serverCount++
+
+		// Count enabled tools on this server
+		if (server.tools) {
+			for (const tool of server.tools) {
+				// Tool is enabled if enabledForPrompt is undefined (default) or true
+				if (tool.enabledForPrompt !== false) {
+					toolCount++
+				}
+			}
+		}
+	}
+
+	return { enabledToolCount: toolCount, enabledServerCount: serverCount }
+}
--- a/packages/types/src/message.ts
+++ b/packages/types/src/message.ts
@ -149,6 +149,7 @@ export function isNonBlockingAsk(ask: ClineAsk): ask is NonBlockingAsk {
 * - `condense_context`: Context condensation/summarization has started
 * - `condense_context_error`: Error occurred during context condensation
 * - `codebase_search_result`: Results from searching the codebase
+ * - `too_many_tools_warning`: Warning that too many MCP tools are enabled, which may confuse the LLM
 */
 export const clineSays = [
 	"error",
@ -180,6 +181,7 @@ export const clineSays = [
 	"sliding_window_truncation",
 	"codebase_search_result",
 	"user_edit_todos",
+	"too_many_tools_warning",
 ] as const

 export const clineSaySchema = z.enum(clineSays)
--- a/src/core/task/Task.ts
+++ b/src/core/task/Task.ts
@ -53,6 +53,8 @@ import {
 	MIN_CHECKPOINT_TIMEOUT_SECONDS,
 	TOOL_PROTOCOL,
 	ConsecutiveMistakeError,
+	MAX_MCP_TOOLS_THRESHOLD,
+	countEnabledMcpTools,
 } from "@roo-code/types"
 import { TelemetryService } from "@roo-code/telemetry"
 import { CloudService, BridgeOrchestrator } from "@roo-code/cloud"
@ -1832,6 +1834,37 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 	// Lifecycle
 	// Start / Resume / Abort / Dispose

+	/**
+	 * Get enabled MCP tools count for this task.
+	 * Returns the count along with the number of servers contributing.
+	 *
+	 * @returns Object with enabledToolCount and enabledServerCount
+	 */
+	private async getEnabledMcpToolsCount(): Promise<{ enabledToolCount: number; enabledServerCount: number }> {
+		try {
+			const provider = this.providerRef.deref()
+			if (!provider) {
+				return { enabledToolCount: 0, enabledServerCount: 0 }
+			}
+
+			const { mcpEnabled } = (await provider.getState()) ?? {}
+			if (!(mcpEnabled ?? true)) {
+				return { enabledToolCount: 0, enabledServerCount: 0 }
+			}
+
+			const mcpHub = await McpServerManager.getInstance(provider.context, provider)
+			if (!mcpHub) {
+				return { enabledToolCount: 0, enabledServerCount: 0 }
+			}
+
+			const servers = mcpHub.getServers()
+			return countEnabledMcpTools(servers)
+		} catch (error) {
+			console.error("[Task#getEnabledMcpToolsCount] Error counting MCP tools:", error)
+			return { enabledToolCount: 0, enabledServerCount: 0 }
+		}
+	}
+
 	private async startTask(task?: string, images?: string[]): Promise<void> {
 		if (this.enableBridge) {
 			try {
@ -1858,6 +1891,24 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		await this.providerRef.deref()?.postStateToWebview()

 		await this.say("text", task, images)
+
+		// Check for too many MCP tools and warn the user
+		const { enabledToolCount, enabledServerCount } = await this.getEnabledMcpToolsCount()
+		if (enabledToolCount > MAX_MCP_TOOLS_THRESHOLD) {
+			await this.say(
+				"too_many_tools_warning",
+				JSON.stringify({
+					toolCount: enabledToolCount,
+					serverCount: enabledServerCount,
+					threshold: MAX_MCP_TOOLS_THRESHOLD,
+				}),
+				undefined,
+				undefined,
+				undefined,
+				undefined,
+				{ isNonInteractive: true },
+			)
+		}
 		this.isInitialized = true

 		let imageBlocks: Anthropic.ImageBlockParam[] = formatResponse.imageBlocks(images)
--- a/webview-ui/src/components/chat/ChatRow.tsx
+++ b/webview-ui/src/components/chat/ChatRow.tsx
@ -32,6 +32,7 @@ import { ReasoningBlock } from "./ReasoningBlock"
 import Thumbnails from "../common/Thumbnails"
 import ImageBlock from "../common/ImageBlock"
 import ErrorRow from "./ErrorRow"
+import WarningRow from "./WarningRow"

 import McpResourceRow from "../mcp/McpResourceRow"

@ -1517,6 +1518,33 @@ export const ChatRowContent = ({
 				case "browser_action_result":
 					// Handled by BrowserSessionRow; prevent raw JSON (action/result) from rendering here
 					return null
+				case "too_many_tools_warning": {
+					const warningData = safeJsonParse<{
+						toolCount: number
+						serverCount: number
+						threshold: number
+					}>(message.text || "{}")
+					if (!warningData) return null
+					const toolsPart = t("chat:tooManyTools.toolsPart", { count: warningData.toolCount })
+					const serversPart = t("chat:tooManyTools.serversPart", { count: warningData.serverCount })
+					return (
+						<WarningRow
+							title={t("chat:tooManyTools.title")}
+							message={t("chat:tooManyTools.messageTemplate", {
+								tools: toolsPart,
+								servers: serversPart,
+								threshold: warningData.threshold,
+							})}
+							actionText={t("chat:tooManyTools.openMcpSettings")}
+							onAction={() =>
+								window.postMessage(
+									{ type: "action", action: "settingsButtonClicked", values: { section: "mcp" } },
+									"*",
+								)
+							}
+						/>
+					)
+				}
 				default:
 					return (
 						<>
--- a/webview-ui/src/components/chat/ErrorRow.tsx
+++ b/webview-ui/src/components/chat/ErrorRow.tsx
@ -266,11 +266,11 @@ export const ErrorRow = memo(
 							</div>
 						</div>
 					)}
-					<div className="ml-2 pl-4 mt-1 pt-1 border-l border-vscode-errorForeground/50">
+					<div className="ml-2 pl-4 mt-1 pt-0.5 border-l border-vscode-errorForeground/50">
 						<p
 							className={
 								messageClassName ||
-								"my-0 font-light whitespace-pre-wrap break-words text-vscode-descriptionForeground"
+								"cursor-default my-0 font-light whitespace-pre-wrap break-words text-vscode-descriptionForeground"
 							}>
 							{message}
 							{formattedErrorDetails && (
--- a/webview-ui/src/components/chat/TooManyToolsWarning.tsx
+++ b/webview-ui/src/components/chat/TooManyToolsWarning.tsx
@ -0,0 +1,39 @@
+import React, { useCallback } from "react"
+import { useAppTranslation } from "@/i18n/TranslationContext"
+import { useTooManyTools } from "@src/hooks/useTooManyTools"
+import WarningRow from "./WarningRow"
+
+/**
+ * Displays a warning when the user has too many MCP tools enabled.
+ * LLMs get confused when offered too many tools, which can lead to errors.
+ *
+ * The warning is shown when:
+ * - The total number of enabled tools across all enabled MCP servers exceeds the threshold
+ *
+ * @example
+ * <TooManyToolsWarning />
+ */
+export const TooManyToolsWarning: React.FC = () => {
+	const { t } = useAppTranslation()
+	const { isOverThreshold, title, message } = useTooManyTools()
+
+	const handleOpenMcpSettings = useCallback(() => {
+		window.postMessage({ type: "action", action: "settingsButtonClicked", values: { section: "mcp" } }, "*")
+	}, [])
+
+	// Don't show warning if under threshold
+	if (!isOverThreshold) {
+		return null
+	}
+
+	return (
+		<WarningRow
+			title={title}
+			message={message}
+			actionText={t("chat:tooManyTools.openMcpSettings")}
+			onAction={handleOpenMcpSettings}
+		/>
+	)
+}
+
+export default TooManyToolsWarning
--- a/webview-ui/src/components/chat/WarningRow.tsx
+++ b/webview-ui/src/components/chat/WarningRow.tsx
@ -0,0 +1,77 @@
+import React from "react"
+import { TriangleAlert, BookOpenText } from "lucide-react"
+import { useAppTranslation } from "@/i18n/TranslationContext"
+import { vscode } from "@src/utils/vscode"
+
+export interface WarningRowProps {
+	title: string
+	message: string
+	docsURL?: string
+	actionText?: string
+	onAction?: () => void
+}
+
+/**
+ * A generic warning row component that displays a warning icon, title, and message.
+ * Optionally includes a documentation link and/or an action link.
+ *
+ * @param title - The warning title displayed in bold
+ * @param message - The warning message displayed below the title
+ * @param docsURL - Optional documentation link URL (shown as "Learn more" with book icon)
+ * @param actionText - Optional text for an action link appended to the message
+ * @param onAction - Optional callback when the action link is clicked
+ *
+ * @example
+ * <WarningRow
+ *   title="Too many tools enabled"
+ *   message="You have 50 tools enabled via 5 MCP servers."
+ *   docsURL="https://docs.example.com/mcp-best-practices"
+ *   actionText="Open MCP Settings"
+ *   onAction={() => openSettings()}
+ * />
+ */
+export const WarningRow: React.FC<WarningRowProps> = ({ title, message, docsURL, actionText, onAction }) => {
+	const { t } = useAppTranslation()
+
+	return (
+		<div className="group pr-2 py-2">
+			<div className="flex items-center justify-between gap-2 break-words">
+				<TriangleAlert className="w-4 text-vscode-editorWarning-foreground shrink-0" />
+				<span className="font-bold text-vscode-editorWarning-foreground grow cursor-default">{title}</span>
+				{docsURL && (
+					<a
+						href={docsURL}
+						className="text-sm flex items-center gap-1 transition-opacity opacity-0 group-hover:opacity-100"
+						onClick={(e) => {
+							e.preventDefault()
+							vscode.postMessage({ type: "openExternal", url: docsURL })
+						}}>
+						<BookOpenText className="size-3 mt-[3px]" />
+						{t("chat:apiRequest.errorMessage.docs")}
+					</a>
+				)}
+			</div>
+			<div className="cursor-default ml-2 pl-4 mt-1 pt-0.5 border-l border-vscode-editorWarning-foreground/50">
+				<p className="my-0 font-light whitespace-pre-wrap break-words text-vscode-descriptionForeground">
+					{message}
+					{actionText && onAction && (
+						<>
+							{" "}
+							<a
+								href="#"
+								className="text-vscode-textLink-foreground hover:text-vscode-textLink-activeForeground cursor-pointer"
+								onClick={(e) => {
+									e.preventDefault()
+									onAction()
+								}}>
+								{actionText}
+							</a>
+						</>
+					)}
+				</p>
+			</div>
+		</div>
+	)
+}
+
+export default WarningRow
--- a/webview-ui/src/components/chat/tests/TooManyToolsWarning.spec.tsx
+++ b/webview-ui/src/components/chat/tests/TooManyToolsWarning.spec.tsx
@ -0,0 +1,296 @@
+import { render, screen, fireEvent } from "@/utils/test-utils"
+import { MAX_MCP_TOOLS_THRESHOLD } from "@roo-code/types"
+
+import { TooManyToolsWarning } from "../TooManyToolsWarning"
+
+// Mock vscode webview messaging
+vi.mock("@/utils/vscode", () => ({
+	vscode: {
+		postMessage: vi.fn(),
+	},
+}))
+
+// Mock ExtensionState context with variable mcpServers
+const mockMcpServers = vi.fn()
+
+vi.mock("@/context/ExtensionStateContext", () => ({
+	useExtensionState: () => ({
+		mcpServers: mockMcpServers(),
+	}),
+}))
+
+// Mock i18n TranslationContext
+vi.mock("@/i18n/TranslationContext", () => ({
+	useAppTranslation: () => ({
+		t: (key: string, params?: Record<string, any>) => {
+			if (key === "chat:tooManyTools.title") {
+				return "Too many tools enabled"
+			}
+			if (key === "chat:tooManyTools.toolsPart") {
+				const count = params?.count ?? 0
+				return count === 1 ? `${count} tool` : `${count} tools`
+			}
+			if (key === "chat:tooManyTools.serversPart") {
+				const count = params?.count ?? 0
+				return count === 1 ? `${count} MCP server` : `${count} MCP servers`
+			}
+			if (key === "chat:tooManyTools.messageTemplate") {
+				return `You have ${params?.tools} enabled via ${params?.servers}. Such a high number can confuse the model and lead to errors. Try to keep it below ${params?.threshold}.`
+			}
+			if (key === "chat:tooManyTools.openMcpSettings") {
+				return "Open MCP Settings"
+			}
+			if (key === "chat:apiRequest.errorMessage.docs") {
+				return "Docs"
+			}
+			return key
+		},
+	}),
+}))
+
+describe("TooManyToolsWarning", () => {
+	beforeEach(() => {
+		vi.clearAllMocks()
+		mockMcpServers.mockReturnValue([])
+	})
+
+	it("does not render when there are no MCP servers", () => {
+		mockMcpServers.mockReturnValue([])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("does not render when tool count is below threshold", () => {
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools: [
+					{ name: "tool1", enabledForPrompt: true },
+					{ name: "tool2", enabledForPrompt: true },
+				],
+			},
+		])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("does not render when tool count equals threshold", () => {
+		// Create tools to exactly match threshold
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD }, (_, i) => ({
+			name: `tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools,
+			},
+		])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("renders warning when tool count exceeds threshold", () => {
+		// Create more tools than the threshold
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 10 }, (_, i) => ({
+			name: `tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools,
+			},
+		])
+
+		render(<TooManyToolsWarning />)
+
+		expect(screen.getByText("Too many tools enabled")).toBeInTheDocument()
+		expect(
+			screen.getByText(
+				`You have ${MAX_MCP_TOOLS_THRESHOLD + 10} tools enabled via 1 MCP server. Such a high number can confuse the model and lead to errors. Try to keep it below ${MAX_MCP_TOOLS_THRESHOLD}.`,
+			),
+		).toBeInTheDocument()
+	})
+
+	it("ignores disabled servers", () => {
+		// Create tools across two servers, one disabled
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 10 }, (_, i) => ({
+			name: `tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "disabledServer",
+				status: "connected",
+				disabled: true, // This server is disabled
+				tools,
+			},
+			{
+				name: "enabledServer",
+				status: "connected",
+				disabled: false,
+				tools: [{ name: "tool1", enabledForPrompt: true }], // Only 1 tool
+			},
+		])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		// Should not render because only 1 tool is on enabled server
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("ignores disconnected servers", () => {
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 10 }, (_, i) => ({
+			name: `tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "disconnectedServer",
+				status: "disconnected", // Not connected
+				disabled: false,
+				tools,
+			},
+		])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("ignores disabled tools", () => {
+		// Create tools with some disabled
+		const enabledTools = Array.from({ length: 20 }, (_, i) => ({
+			name: `enabledTool${i}`,
+			enabledForPrompt: true,
+		}))
+		const disabledTools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 10 }, (_, i) => ({
+			name: `disabledTool${i}`,
+			enabledForPrompt: false, // These are disabled
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools: [...enabledTools, ...disabledTools],
+			},
+		])
+
+		const { container } = render(<TooManyToolsWarning />)
+
+		// Should not render because only 20 tools are enabled
+		expect(container.firstChild).toBeNull()
+	})
+
+	it("treats tools with undefined enabledForPrompt as enabled", () => {
+		// Create tools without enabledForPrompt set (default behavior is enabled)
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 5 }, (_, i) => ({
+			name: `tool${i}`,
+			// enabledForPrompt is undefined, which means enabled by default
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools,
+			},
+		])
+
+		render(<TooManyToolsWarning />)
+
+		expect(screen.getByText("Too many tools enabled")).toBeInTheDocument()
+	})
+
+	it("counts tools across multiple servers", () => {
+		// Create tools across multiple servers
+		const tools1 = Array.from({ length: 35 }, (_, i) => ({
+			name: `server1tool${i}`,
+			enabledForPrompt: true,
+		}))
+		const tools2 = Array.from({ length: 30 }, (_, i) => ({
+			name: `server2tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools: tools1,
+			},
+			{
+				name: "server2",
+				status: "connected",
+				disabled: false,
+				tools: tools2,
+			},
+		])
+
+		render(<TooManyToolsWarning />)
+
+		// 35 + 30 = 65 tools > 60 threshold
+		expect(screen.getByText("Too many tools enabled")).toBeInTheDocument()
+		expect(
+			screen.getByText(
+				`You have 65 tools enabled via 2 MCP servers. Such a high number can confuse the model and lead to errors. Try to keep it below ${MAX_MCP_TOOLS_THRESHOLD}.`,
+			),
+		).toBeInTheDocument()
+	})
+
+	it("renders MCP settings link and opens settings when clicked", () => {
+		const mockWindowPostMessage = vi.spyOn(window, "postMessage")
+
+		// Create more tools than the threshold
+		const tools = Array.from({ length: MAX_MCP_TOOLS_THRESHOLD + 10 }, (_, i) => ({
+			name: `tool${i}`,
+			enabledForPrompt: true,
+		}))
+
+		mockMcpServers.mockReturnValue([
+			{
+				name: "server1",
+				status: "connected",
+				disabled: false,
+				tools,
+			},
+		])
+
+		render(<TooManyToolsWarning />)
+
+		// Verify the link is rendered
+		const settingsLink = screen.getByText("Open MCP Settings")
+		expect(settingsLink).toBeInTheDocument()
+
+		// Click the link and verify it posts the message
+		fireEvent.click(settingsLink)
+
+		expect(mockWindowPostMessage).toHaveBeenCalledWith(
+			{ type: "action", action: "settingsButtonClicked", values: { section: "mcp" } },
+			"*",
+		)
+
+		mockWindowPostMessage.mockRestore()
+	})
+})
--- a/webview-ui/src/components/chat/tests/WarningRow.spec.tsx
+++ b/webview-ui/src/components/chat/tests/WarningRow.spec.tsx
@ -0,0 +1,109 @@
+import { render, screen, fireEvent } from "@/utils/test-utils"
+import { vscode } from "@/utils/vscode"
+
+import { WarningRow } from "../WarningRow"
+
+// Mock vscode webview messaging
+vi.mock("@/utils/vscode", () => ({
+	vscode: {
+		postMessage: vi.fn(),
+	},
+}))
+
+// Mock i18n TranslationContext
+vi.mock("@/i18n/TranslationContext", () => ({
+	useAppTranslation: () => ({
+		t: (key: string) => {
+			const map: Record<string, string> = {
+				"chat:apiRequest.errorMessage.docs": "Docs",
+			}
+			return map[key] ?? key
+		},
+	}),
+}))
+
+describe("WarningRow", () => {
+	beforeEach(() => {
+		vi.clearAllMocks()
+	})
+
+	it("renders title and message", () => {
+		render(<WarningRow title="Test Warning" message="This is a test warning message" />)
+
+		expect(screen.getByText("Test Warning")).toBeInTheDocument()
+		expect(screen.getByText("This is a test warning message")).toBeInTheDocument()
+	})
+
+	it("does not render docs link when docsURL is not provided", () => {
+		render(<WarningRow title="Test Warning" message="This is a test message" />)
+
+		expect(screen.queryByText("Docs")).not.toBeInTheDocument()
+	})
+
+	it("renders docs link when docsURL is provided", () => {
+		render(<WarningRow title="Test Warning" message="This is a test message" docsURL="https://docs.example.com" />)
+
+		const docsLink = screen.getByText("Docs")
+		expect(docsLink).toBeInTheDocument()
+	})
+
+	it("opens external URL when docs link is clicked", () => {
+		const mockPostMessage = vi.mocked(vscode.postMessage)
+
+		render(<WarningRow title="Test Warning" message="This is a test message" docsURL="https://docs.example.com" />)
+
+		const docsLink = screen.getByText("Docs")
+		fireEvent.click(docsLink)
+
+		expect(mockPostMessage).toHaveBeenCalledWith({
+			type: "openExternal",
+			url: "https://docs.example.com",
+		})
+	})
+
+	it("renders warning icon", () => {
+		const { container } = render(<WarningRow title="Test Warning" message="This is a test message" />)
+
+		// TriangleAlert icon should be present (as an SVG element)
+		const warningIcon = container.querySelector("svg")
+		expect(warningIcon).toBeInTheDocument()
+	})
+
+	it("does not render action link when actionText and onAction are not provided", () => {
+		render(<WarningRow title="Test Warning" message="This is a test message" />)
+
+		expect(screen.queryByText("Open Settings")).not.toBeInTheDocument()
+	})
+
+	it("renders action link when actionText and onAction are provided", () => {
+		const mockOnAction = vi.fn()
+		render(
+			<WarningRow
+				title="Test Warning"
+				message="This is a test message"
+				actionText="Open Settings"
+				onAction={mockOnAction}
+			/>,
+		)
+
+		const actionLink = screen.getByText("Open Settings")
+		expect(actionLink).toBeInTheDocument()
+	})
+
+	it("calls onAction when action link is clicked", () => {
+		const mockOnAction = vi.fn()
+		render(
+			<WarningRow
+				title="Test Warning"
+				message="This is a test message"
+				actionText="Open Settings"
+				onAction={mockOnAction}
+			/>,
+		)
+
+		const actionLink = screen.getByText("Open Settings")
+		fireEvent.click(actionLink)
+
+		expect(mockOnAction).toHaveBeenCalledTimes(1)
+	})
+})
--- a/webview-ui/src/components/mcp/McpView.tsx
+++ b/webview-ui/src/components/mcp/McpView.tsx
@ -13,6 +13,7 @@ import type { McpServer } from "@roo-code/types"
 import { vscode } from "@src/utils/vscode"
 import { useExtensionState } from "@src/context/ExtensionStateContext"
 import { useAppTranslation } from "@src/i18n/TranslationContext"
+import { useTooManyTools } from "@src/hooks/useTooManyTools"
 import {
 	Button,
 	Dialog,
@ -43,6 +44,7 @@ const McpView = () => {
 	} = useExtensionState()

 	const { t } = useAppTranslation()
+	const { isOverThreshold, title, message } = useTooManyTools()

 	return (
 		<div>
@ -99,6 +101,31 @@ const McpView = () => {
 							</div>
 						</div>

+						{/* Too Many Tools Warning */}
+						{isOverThreshold && (
+							<div style={{ marginBottom: 15 }}>
+								<div
+									style={{
+										display: "flex",
+										alignItems: "center",
+										gap: "6px",
+										fontWeight: "500",
+										color: "var(--vscode-editorWarning-foreground)",
+										marginBottom: "5px",
+									}}>
+									<span className="codicon codicon-warning" />
+									{title}
+								</div>
+								<div
+									style={{
+										fontSize: "12px",
+										color: "var(--vscode-descriptionForeground)",
+									}}>
+									{message}
+								</div>
+							</div>
+						)}
+
 						{/* Server List */}
 						{servers.length > 0 && (
 							<div style={{ display: "flex", flexDirection: "column", gap: "10px" }}>
--- a/webview-ui/src/hooks/useTooManyTools.ts
+++ b/webview-ui/src/hooks/useTooManyTools.ts
@ -0,0 +1,57 @@
+import { useMemo } from "react"
+import { useExtensionState } from "@src/context/ExtensionStateContext"
+import { useAppTranslation } from "@src/i18n/TranslationContext"
+import { MAX_MCP_TOOLS_THRESHOLD, countEnabledMcpTools } from "@roo-code/types"
+
+export interface TooManyToolsInfo {
+	/** Number of enabled and connected MCP servers */
+	enabledServerCount: number
+	/** Total number of enabled tools across all enabled servers */
+	enabledToolCount: number
+	/** Whether the tool count exceeds the threshold */
+	isOverThreshold: boolean
+	/** The maximum recommended threshold */
+	threshold: number
+	/** Localized title string */
+	title: string
+	/** Localized message string */
+	message: string
+}
+
+/**
+ * Hook that calculates tool counts and provides localized warning messages.
+ * Used by TooManyToolsWarning components in both chat and MCP settings views.
+ *
+ * @returns Tool count information and localized messages
+ *
+ * @example
+ * const { isOverThreshold, title, message } = useTooManyTools()
+ * if (isOverThreshold) {
+ *   // Show warning
+ * }
+ */
+export function useTooManyTools(): TooManyToolsInfo {
+	const { t } = useAppTranslation()
+	const { mcpServers } = useExtensionState()
+
+	const { enabledServerCount, enabledToolCount } = useMemo(() => countEnabledMcpTools(mcpServers), [mcpServers])
+
+	const isOverThreshold = enabledToolCount > MAX_MCP_TOOLS_THRESHOLD
+
+	const toolsPart = t("chat:tooManyTools.toolsPart", { count: enabledToolCount })
+	const serversPart = t("chat:tooManyTools.serversPart", { count: enabledServerCount })
+	const message = t("chat:tooManyTools.messageTemplate", {
+		tools: toolsPart,
+		servers: serversPart,
+		threshold: MAX_MCP_TOOLS_THRESHOLD,
+	})
+
+	return {
+		enabledServerCount,
+		enabledToolCount,
+		isOverThreshold,
+		threshold: MAX_MCP_TOOLS_THRESHOLD,
+		title: t("chat:tooManyTools.title"),
+		message,
+	}
+}
--- a/webview-ui/src/i18n/locales/ca/chat.json
+++ b/webview-ui/src/i18n/locales/ca/chat.json
@ -492,5 +492,14 @@
 		"updated": "S'ha actualitzat la llista de tasques pendents",
 		"completed": "Completat",
 		"started": "Iniciat"
+	},
+	"tooManyTools": {
+		"title": "Massa eines habilitades",
+		"toolsPart_one": "{{count}} eina",
+		"toolsPart_other": "{{count}} eines",
+		"serversPart_one": "{{count}} servidor MCP",
+		"serversPart_other": "{{count}} servidors MCP",
+		"messageTemplate": "Tens {{tools}} habilitades via {{servers}}. Un nombre tant alt pot confondre el model i portar a errors. Intenta mantenir-lo per sota de {{threshold}}.",
+		"openMcpSettings": "Obrir configuració de MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/de/chat.json
+++ b/webview-ui/src/i18n/locales/de/chat.json
@ -492,5 +492,14 @@
 		"updated": "Die To-Do-Liste wurde aktualisiert",
 		"completed": "Abgeschlossen",
 		"started": "Gestartet"
+	},
+	"tooManyTools": {
+		"title": "Zu viele Tools aktiviert",
+		"toolsPart_one": "{{count}} Tool",
+		"toolsPart_other": "{{count}} Tools",
+		"serversPart_one": "{{count}} MCP-Server",
+		"serversPart_other": "{{count}} MCP-Server",
+		"messageTemplate": "Du hast {{tools}} über {{servers}} aktiviert. Eine so hohe Anzahl kann das Modell verwirren und zu Fehlern führen. Versuche, es unter {{threshold}} zu halten.",
+		"openMcpSettings": "MCP-Einstellungen öffnen"
 	}
 }
--- a/webview-ui/src/i18n/locales/en/chat.json
+++ b/webview-ui/src/i18n/locales/en/chat.json
@ -484,5 +484,14 @@
 		"updated": "Updated the to-do list",
 		"completed": "Completed",
 		"started": "Started"
+	},
+	"tooManyTools": {
+		"title": "Too many tools enabled",
+		"toolsPart_one": "{{count}} tool",
+		"toolsPart_other": "{{count}} tools",
+		"serversPart_one": "{{count}} MCP server",
+		"serversPart_other": "{{count}} MCP servers",
+		"messageTemplate": "You have {{tools}} enabled via {{servers}}. Such a high number can confuse the model and lead to errors. Try to keep it below {{threshold}}.",
+		"openMcpSettings": "Open MCP Settings"
 	}
 }
--- a/webview-ui/src/i18n/locales/es/chat.json
+++ b/webview-ui/src/i18n/locales/es/chat.json
@ -492,5 +492,14 @@
 		"updated": "Se actualizó la lista de tareas pendientes",
 		"completed": "Completado",
 		"started": "Iniciado"
+	},
+	"tooManyTools": {
+		"title": "Demasiadas herramientas habilitadas",
+		"toolsPart_one": "{{count}} herramienta",
+		"toolsPart_other": "{{count}} herramientas",
+		"serversPart_one": "{{count}} servidor MCP",
+		"serversPart_other": "{{count}} servidores MCP",
+		"messageTemplate": "Tienes {{tools}} habilitadas a través de {{servers}}. Un número tan alto puede confundir al modelo y llevar a errores. Intenta mantenerlo por debajo de {{threshold}}.",
+		"openMcpSettings": "Abrir configuración de MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/fr/chat.json
+++ b/webview-ui/src/i18n/locales/fr/chat.json
@ -492,5 +492,14 @@
 		"updated": "La liste des tâches a été mise à jour",
 		"completed": "Terminé",
 		"started": "Commencé"
+	},
+	"tooManyTools": {
+		"title": "Trop d'outils activés",
+		"toolsPart_one": "{{count}} outil",
+		"toolsPart_other": "{{count}} outils",
+		"serversPart_one": "{{count}} serveur MCP",
+		"serversPart_other": "{{count}} serveurs MCP",
+		"messageTemplate": "Tu as {{tools}} activés via {{servers}}. Un nombre aussi élevé peut confondre le modèle et entraîner des erreurs. Essaie de le maintenir en dessous de {{threshold}}.",
+		"openMcpSettings": "Ouvrir les paramètres MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/hi/chat.json
+++ b/webview-ui/src/i18n/locales/hi/chat.json
@ -492,5 +492,14 @@
 		"updated": "टू-डू सूची अपडेट की गई",
 		"completed": "पूरा हुआ",
 		"started": "शुरू हुआ"
+	},
+	"tooManyTools": {
+		"title": "बहुत सारे उपकरण सक्षम हैं",
+		"toolsPart_one": "{{count}} उपकरण",
+		"toolsPart_other": "{{count}} उपकरण",
+		"serversPart_one": "{{count}} MCP सर्वर",
+		"serversPart_other": "{{count}} MCP सर्वर",
+		"messageTemplate": "आपके पास {{servers}} के माध्यम से {{tools}} सक्षम हैं। इतनी अधिक संख्या मॉडल को भ्रमित कर सकती है और त्रुटियों का कारण बन सकती है। इसे {{threshold}} से नीचे रखने का प्रयास करें।",
+		"openMcpSettings": "MCP सेटिंग्स खोलें"
 	}
 }
--- a/webview-ui/src/i18n/locales/id/chat.json
+++ b/webview-ui/src/i18n/locales/id/chat.json
@ -498,5 +498,14 @@
 		"updated": "Memperbarui daftar to-do",
 		"completed": "Selesai",
 		"started": "Dimulai"
+	},
+	"tooManyTools": {
+		"title": "Terlalu banyak alat diaktifkan",
+		"toolsPart_one": "{{count}} alat",
+		"toolsPart_other": "{{count}} alat",
+		"serversPart_one": "{{count}} server MCP",
+		"serversPart_other": "{{count}} server MCP",
+		"messageTemplate": "Anda memiliki {{tools}} diaktifkan melalui {{servers}}. Jumlah yang begitu besar dapat membingungkan model dan menyebabkan kesalahan. Cobalah untuk menjaganya di bawah {{threshold}}.",
+		"openMcpSettings": "Buka Pengaturan MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/it/chat.json
+++ b/webview-ui/src/i18n/locales/it/chat.json
@ -492,5 +492,14 @@
 		"updated": "Aggiornata la lista delle cose da fare",
 		"completed": "Completato",
 		"started": "Iniziato"
+	},
+	"tooManyTools": {
+		"title": "Troppi strumenti abilitati",
+		"toolsPart_one": "{{count}} strumento",
+		"toolsPart_other": "{{count}} strumenti",
+		"serversPart_one": "{{count}} server MCP",
+		"serversPart_other": "{{count}} server MCP",
+		"messageTemplate": "Hai {{tools}} abilitate via {{servers}}. Un numero così alto può confondere il modello e portare a errori. Prova a mantenerlo sotto {{threshold}}.",
+		"openMcpSettings": "Apri impostazioni MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/ja/chat.json
+++ b/webview-ui/src/i18n/locales/ja/chat.json
@ -492,5 +492,14 @@
 		"updated": "To-Doリストを更新しました",
 		"completed": "完了",
 		"started": "開始"
+	},
+	"tooManyTools": {
+		"title": "有効になっているツールが多すぎます",
+		"toolsPart_one": "{{count}} ツール",
+		"toolsPart_other": "{{count}} ツール",
+		"serversPart_one": "{{count}} MCP サーバー",
+		"serversPart_other": "{{count}} MCP サーバー",
+		"messageTemplate": "{{servers}}経由で{{tools}}が有効になっています。このような高い数は、モデルを混乱させてエラーを引き起こす可能性があります。{{threshold}}以下に保つようにしてください。",
+		"openMcpSettings": "MCP 設定を開く"
 	}
 }
--- a/webview-ui/src/i18n/locales/ko/chat.json
+++ b/webview-ui/src/i18n/locales/ko/chat.json
@ -492,5 +492,14 @@
 		"updated": "할 일 목록을 업데이트했습니다",
 		"completed": "완료됨",
 		"started": "시작됨"
+	},
+	"tooManyTools": {
+		"title": "활성화된 도구가 너무 많습니다",
+		"toolsPart_one": "{{count}}개 도구",
+		"toolsPart_other": "{{count}}개 도구",
+		"serversPart_one": "{{count}}개 MCP 서버",
+		"serversPart_other": "{{count}}개 MCP 서버",
+		"messageTemplate": "{{servers}}를 통해 {{tools}}가 활성화되어 있습니다. 이렇게 많은 수의 도구는 모델을 혼동시키고 오류를 유발할 수 있습니다. {{threshold}} 이하로 유지하도록 노력하세요.",
+		"openMcpSettings": "MCP 설정 열기"
 	}
 }
--- a/webview-ui/src/i18n/locales/nl/chat.json
+++ b/webview-ui/src/i18n/locales/nl/chat.json
@ -492,5 +492,14 @@
 		"updated": "De to-do-lijst is bijgewerkt",
 		"completed": "Voltooid",
 		"started": "Gestart"
+	},
+	"tooManyTools": {
+		"title": "Te veel tools ingeschakeld",
+		"toolsPart_one": "{{count}} tool",
+		"toolsPart_other": "{{count}} tools",
+		"serversPart_one": "{{count}} MCP server",
+		"serversPart_other": "{{count}} MCP servers",
+		"messageTemplate": "Je hebt {{tools}} ingeschakeld via {{servers}}. Zoveel tools kunnen het model verwarren en tot fouten leiden. Probeer dit onder {{threshold}} te houden.",
+		"openMcpSettings": "MCP-instellingen openen"
 	}
 }
--- a/webview-ui/src/i18n/locales/pl/chat.json
+++ b/webview-ui/src/i18n/locales/pl/chat.json
@ -492,5 +492,14 @@
 		"updated": "Zaktualizowano listę zadań do wykonania",
 		"completed": "Ukończono",
 		"started": "Rozpoczęto"
+	},
+	"tooManyTools": {
+		"title": "Włączono zbyt wiele narzędzi",
+		"toolsPart_one": "{{count}} narzędzie",
+		"toolsPart_other": "{{count}} narzędzi",
+		"serversPart_one": "{{count}} serwer MCP",
+		"serversPart_other": "{{count}} serwerów MCP",
+		"messageTemplate": "Masz {{tools}} włączonych przez {{servers}}. Taka duża liczba może zamieszać model i prowadzić do błędów. Staraj się, aby była poniżej {{threshold}}.",
+		"openMcpSettings": "Otwórz ustawienia MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/pt-BR/chat.json
+++ b/webview-ui/src/i18n/locales/pt-BR/chat.json
@ -492,5 +492,14 @@
 		"updated": "A lista de tarefas foi atualizada",
 		"completed": "Concluído",
 		"started": "Iniciado"
+	},
+	"tooManyTools": {
+		"title": "Muitas ferramentas habilitadas",
+		"toolsPart_one": "{{count}} ferramenta",
+		"toolsPart_other": "{{count}} ferramentas",
+		"serversPart_one": "{{count}} servidor MCP",
+		"serversPart_other": "{{count}} servidores MCP",
+		"messageTemplate": "Você tem {{tools}} habilitadas via {{servers}}. Um número tão alto pode confundir o modelo e levar a erros. Tente mantê-lo abaixo de {{threshold}}.",
+		"openMcpSettings": "Abrir Configurações MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/ru/chat.json
+++ b/webview-ui/src/i18n/locales/ru/chat.json
@ -493,5 +493,14 @@
 		"updated": "Список задач обновлен",
 		"completed": "Завершено",
 		"started": "Начато"
+	},
+	"tooManyTools": {
+		"title": "Включено слишком много инструментов",
+		"toolsPart_one": "{{count}} инструмент",
+		"toolsPart_other": "{{count}} инструментов",
+		"serversPart_one": "{{count}} сервер MCP",
+		"serversPart_other": "{{count}} серверов MCP",
+		"messageTemplate": "У тебя включено {{tools}} через {{servers}}. Такое большое количество может сбить модель с толку и привести к ошибкам. Постарайся держать это ниже {{threshold}}.",
+		"openMcpSettings": "Открыть настройки MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/tr/chat.json
+++ b/webview-ui/src/i18n/locales/tr/chat.json
@ -493,5 +493,14 @@
 		"updated": "Yapılacaklar listesi güncellendi",
 		"completed": "Tamamlandı",
 		"started": "Başladı"
+	},
+	"tooManyTools": {
+		"title": "Çok fazla araç etkinleştirildi",
+		"toolsPart_one": "{{count}} araç",
+		"toolsPart_other": "{{count}} araç",
+		"serversPart_one": "{{count}} MCP sunucusu",
+		"serversPart_other": "{{count}} MCP sunucusu",
+		"messageTemplate": "{{servers}} üzerinden {{tools}} etkinleştirilmiş durumda. Bu kadar fazlası modeli kafası karışabilir ve hatalara neden olabilir. {{threshold}} altında tutmaya çalış.",
+		"openMcpSettings": "MCP Ayarlarını Aç"
 	}
 }
--- a/webview-ui/src/i18n/locales/vi/chat.json
+++ b/webview-ui/src/i18n/locales/vi/chat.json
@ -493,5 +493,14 @@
 		"updated": "Đã cập nhật danh sách công việc",
 		"completed": "Đã hoàn thành",
 		"started": "Đã bắt đầu"
+	},
+	"tooManyTools": {
+		"title": "Đã bật quá nhiều công cụ",
+		"toolsPart_one": "{{count}} công cụ",
+		"toolsPart_other": "{{count}} công cụ",
+		"serversPart_one": "{{count}} máy chủ MCP",
+		"serversPart_other": "{{count}} máy chủ MCP",
+		"messageTemplate": "Bạn đã bật {{tools}} qua {{servers}}. Số lượng lớn như vậy có thể khiến mô hình bối rối và dẫn đến lỗi. Cố gắng giữ nó dưới {{threshold}}.",
+		"openMcpSettings": "Mở cài đặt MCP"
 	}
 }
--- a/webview-ui/src/i18n/locales/zh-CN/chat.json
+++ b/webview-ui/src/i18n/locales/zh-CN/chat.json
@ -493,5 +493,14 @@
 		"updated": "已更新待办事项列表",
 		"completed": "已完成",
 		"started": "已开始"
+	},
+	"tooManyTools": {
+		"title": "启用的工具过多",
+		"toolsPart_one": "{{count}} 个工具",
+		"toolsPart_other": "{{count}} 个工具",
+		"serversPart_one": "{{count}} 个 MCP 服务",
+		"serversPart_other": "{{count}} 个 MCP 服务",
+		"messageTemplate": "你通过 {{servers}} 启用了 {{tools}}。这么多数量会混淆模型并导致错误。建议将其保持在 {{threshold}} 以下。",
+		"openMcpSettings": "打开 MCP 设置"
 	}
 }
--- a/webview-ui/src/i18n/locales/zh-TW/chat.json
+++ b/webview-ui/src/i18n/locales/zh-TW/chat.json
@ -493,5 +493,14 @@
 		"updated": "已更新待辦事項列表",
 		"completed": "已完成",
 		"started": "已開始"
+	},
+	"tooManyTools": {
+		"title": "啟用的工具過多",
+		"toolsPart_one": "{{count}} 個工具",
+		"toolsPart_other": "{{count}} 個工具",
+		"serversPart_one": "{{count}} 個 MCP 伺服器",
+		"serversPart_other": "{{count}} 個 MCP 伺服器",
+		"messageTemplate": "你已啟用 {{tools}}（透過 {{servers}}）。這麼多的工具可能會混淆模型並導致錯誤。請嘗試保持在 {{threshold}} 以下。",
+		"openMcpSettings": "開啟 MCP 設定"
 	}
 }