diff --git a/packages/types/src/global-settings.ts b/packages/types/src/global-settings.ts
index f5e9fc32bd..52341cd49f 100644
--- a/packages/types/src/global-settings.ts
+++ b/packages/types/src/global-settings.ts
@@ -29,6 +29,20 @@ export const DEFAULT_WRITE_DELAY_MS = 1000
  */
 export const DEFAULT_TERMINAL_OUTPUT_CHARACTER_LIMIT = 50_000
 
+/**
+ * DeniedCommand type - can be either a string (for backward compatibility)
+ * or an object with prefix and optional custom message
+ */
+export const deniedCommandSchema = z.union([
+	z.string(),
+	z.object({
+		prefix: z.string(),
+		message: z.string().optional(),
+	}),
+])
+
+export type DeniedCommand = z.infer<typeof deniedCommandSchema>
+
 /**
  * GlobalSettings
  */
@@ -63,7 +77,7 @@ export const globalSettingsSchema = z.object({
 	followupAutoApproveTimeoutMs: z.number().optional(),
 	alwaysAllowUpdateTodoList: z.boolean().optional(),
 	allowedCommands: z.array(z.string()).optional(),
-	deniedCommands: z.array(z.string()).optional(),
+	deniedCommands: z.array(deniedCommandSchema).optional(),
 	commandExecutionTimeout: z.number().optional(),
 	commandTimeoutAllowlist: z.array(z.string()).optional(),
 	preventCompletionWithOpenTodos: z.boolean().optional(),
diff --git a/src/core/webview/ClineProvider.ts b/src/core/webview/ClineProvider.ts
index 274060a19b..2a0d6a755e 100644
--- a/src/core/webview/ClineProvider.ts
+++ b/src/core/webview/ClineProvider.ts
@@ -1498,8 +1498,62 @@ export class ClineProvider
 	 * Merges denied commands from global state and workspace configuration
 	 * with proper validation and deduplication
 	 */
-	private mergeDeniedCommands(globalStateCommands?: string[]): string[] {
-		return this.mergeCommandLists("deniedCommands", "denied", globalStateCommands)
+	private mergeDeniedCommands(
+		globalStateCommands?: (string | { prefix: string; message?: string })[],
+	): (string | { prefix: string; message?: string })[] {
+		try {
+			// Validate and sanitize global state commands
+			const validGlobalCommands = Array.isArray(globalStateCommands)
+				? globalStateCommands.filter((cmd) => {
+						if (typeof cmd === "string") {
+							return cmd.trim().length > 0
+						} else if (typeof cmd === "object" && cmd !== null && "prefix" in cmd) {
+							return typeof cmd.prefix === "string" && cmd.prefix.trim().length > 0
+						}
+						return false
+					})
+				: []
+
+			// Get workspace configuration commands
+			const workspaceCommands =
+				vscode.workspace
+					.getConfiguration(Package.name)
+					.get<(string | { prefix: string; message?: string })[]>("deniedCommands") || []
+
+			// Validate and sanitize workspace commands
+			const validWorkspaceCommands = Array.isArray(workspaceCommands)
+				? workspaceCommands.filter((cmd) => {
+						if (typeof cmd === "string") {
+							return cmd.trim().length > 0
+						} else if (typeof cmd === "object" && cmd !== null && "prefix" in cmd) {
+							return typeof cmd.prefix === "string" && cmd.prefix.trim().length > 0
+						}
+						return false
+					})
+				: []
+
+			// Combine and deduplicate commands
+			// Global state takes precedence over workspace configuration
+			const prefixMap = new Map<string, string | { prefix: string; message?: string }>()
+
+			// Add workspace commands first
+			validWorkspaceCommands.forEach((cmd) => {
+				const prefix = typeof cmd === "string" ? cmd : cmd.prefix
+				prefixMap.set(prefix, cmd)
+			})
+
+			// Add global commands (overwriting workspace if same prefix)
+			validGlobalCommands.forEach((cmd) => {
+				const prefix = typeof cmd === "string" ? cmd : cmd.prefix
+				prefixMap.set(prefix, cmd)
+			})
+
+			return Array.from(prefixMap.values())
+		} catch (error) {
+			console.error(`Error merging denied commands:`, error)
+			// Return empty array as fallback to prevent crashes
+			return []
+		}
 	}
 
 	/**
diff --git a/src/core/webview/webviewMessageHandler.ts b/src/core/webview/webviewMessageHandler.ts
index f5dc6a467f..9ffa85fd4e 100644
--- a/src/core/webview/webviewMessageHandler.ts
+++ b/src/core/webview/webviewMessageHandler.ts
@@ -12,6 +12,7 @@ import {
 	type GlobalState,
 	type ClineMessage,
 	TelemetryEventName,
+	type DeniedCommand,
 } from "@roo-code/types"
 import { CloudService } from "@roo-code/cloud"
 import { TelemetryService } from "@roo-code/telemetry"
@@ -751,7 +752,7 @@ export const webviewMessageHandler = async (
 				? commands.filter((cmd) => typeof cmd === "string" && cmd.trim().length > 0)
 				: []
 
-			await updateGlobalState("allowedCommands", validCommands)
+			await updateGlobalState("allowedCommands", validCommands as string[])
 
 			// Also update workspace settings.
 			await vscode.workspace
@@ -761,10 +762,18 @@ export const webviewMessageHandler = async (
 			break
 		}
 		case "deniedCommands": {
-			// Validate and sanitize the commands array
+			// Validate and sanitize the commands array - now supports both string and object format
 			const commands = message.commands ?? []
 			const validCommands = Array.isArray(commands)
-				? commands.filter((cmd) => typeof cmd === "string" && cmd.trim().length > 0)
+				? commands.filter((cmd): cmd is string | DeniedCommand => {
+						if (typeof cmd === "string") {
+							return cmd.trim().length > 0
+						} else if (typeof cmd === "object" && cmd !== null && "prefix" in cmd) {
+							// Validate object format
+							return typeof cmd.prefix === "string" && cmd.prefix.trim().length > 0
+						}
+						return false
+					})
 				: []
 
 			await updateGlobalState("deniedCommands", validCommands)
@@ -772,7 +781,7 @@ export const webviewMessageHandler = async (
 			// Also update workspace settings.
 			await vscode.workspace
 				.getConfiguration(Package.name)
-				.update("deniedCommands", validCommands, vscode.ConfigurationTarget.Global)
+				.update("deniedCommands", validCommands as any, vscode.ConfigurationTarget.Global)
 
 			break
 		}
diff --git a/src/package.json b/src/package.json
index dab031404d..b7d1dd41bb 100644
--- a/src/package.json
+++ b/src/package.json
@@ -333,7 +333,28 @@
 				"roo-cline.deniedCommands": {
 					"type": "array",
 					"items": {
-						"type": "string"
+						"oneOf": [
+							{
+								"type": "string"
+							},
+							{
+								"type": "object",
+								"properties": {
+									"prefix": {
+										"type": "string",
+										"description": "The command prefix to deny"
+									},
+									"message": {
+										"type": "string",
+										"description": "Custom message to show when this command is denied"
+									}
+								},
+								"required": [
+									"prefix"
+								],
+								"additionalProperties": false
+							}
+						]
 					},
 					"default": [],
 					"description": "%commands.deniedCommands.description%"
diff --git a/src/shared/WebviewMessage.ts b/src/shared/WebviewMessage.ts
index cb8759d851..33fa6cad36 100644
--- a/src/shared/WebviewMessage.ts
+++ b/src/shared/WebviewMessage.ts
@@ -7,6 +7,7 @@ import type {
 	InstallMarketplaceItemOptions,
 	MarketplaceItem,
 	ShareVisibility,
+	DeniedCommand,
 } from "@roo-code/types"
 import { marketplaceItemSchema } from "@roo-code/types"
 
@@ -221,7 +222,7 @@ export interface WebviewMessage {
 	images?: string[]
 	bool?: boolean
 	value?: number
-	commands?: string[]
+	commands?: string[] | DeniedCommand[]
 	audioType?: AudioType
 	serverName?: string
 	toolName?: string
diff --git a/webview-ui/src/components/chat/ChatView.tsx b/webview-ui/src/components/chat/ChatView.tsx
index e73ac67701..c0556e98d7 100644
--- a/webview-ui/src/components/chat/ChatView.tsx
+++ b/webview-ui/src/components/chat/ChatView.tsx
@@ -27,7 +27,7 @@ import { vscode } from "@src/utils/vscode"
 import {
 	getCommandDecision,
 	CommandDecision,
-	findLongestPrefixMatch,
+	findLongestDeniedMatch,
 	parseCommand,
 } from "@src/utils/command-validation"
 import { useTranslation } from "react-i18next"
@@ -1077,17 +1077,17 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 		[getCommandDecisionForMessage],
 	)
 
-	// Helper function to get the denied prefix for a command
-	const getDeniedPrefix = useCallback(
-		(command: string): string | null => {
+	// Helper function to get the denied command info (prefix and optional message) for a command
+	const getDeniedCommandInfo = useCallback(
+		(command: string): { prefix: string; message?: string } | null => {
 			if (!command || !deniedCommands?.length) return null
 
 			// Parse the command into sub-commands and check each one
 			const subCommands = parseCommand(command)
 			for (const cmd of subCommands) {
-				const deniedMatch = findLongestPrefixMatch(cmd, deniedCommands)
-				if (deniedMatch) {
-					return deniedMatch
+				const deniedMatch = findLongestDeniedMatch(cmd, deniedCommands)
+				if (deniedMatch.prefix) {
+					return deniedMatch as { prefix: string; message?: string }
 				}
 			}
 			return null
@@ -1606,11 +1606,12 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 		const autoApproveOrReject = async () => {
 			// Check for auto-reject first (commands that should be denied)
 			if (lastMessage?.ask === "command" && isDeniedCommand(lastMessage)) {
-				// Get the denied prefix for the localized message
-				const deniedPrefix = getDeniedPrefix(lastMessage.text || "")
-				if (deniedPrefix) {
-					// Create the localized auto-deny message and send it with the rejection
-					const autoDenyMessage = tSettings("autoApprove.execute.autoDenied", { prefix: deniedPrefix })
+				// Get the denied command info (prefix and optional custom message)
+				const deniedInfo = getDeniedCommandInfo(lastMessage.text || "")
+				if (deniedInfo) {
+					// Use custom message if provided, otherwise use the default localized message
+					const autoDenyMessage =
+						deniedInfo.message || tSettings("autoApprove.execute.autoDenied", { prefix: deniedInfo.prefix })
 
 					vscode.postMessage({
 						type: "askResponse",
@@ -1710,7 +1711,7 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 		handleSuggestionClickInRow,
 		isAllowedCommand,
 		isDeniedCommand,
-		getDeniedPrefix,
+		getDeniedCommandInfo,
 		tSettings,
 	])
 
diff --git a/webview-ui/src/components/chat/CommandExecution.tsx b/webview-ui/src/components/chat/CommandExecution.tsx
index c5844bd542..b287372b8b 100644
--- a/webview-ui/src/components/chat/CommandExecution.tsx
+++ b/webview-ui/src/components/chat/CommandExecution.tsx
@@ -15,7 +15,7 @@ import { cn } from "@src/lib/utils"
 import { Button } from "@src/components/ui"
 import CodeBlock from "../common/CodeBlock"
 import { CommandPatternSelector } from "./CommandPatternSelector"
-import { parseCommand } from "../../utils/command-validation"
+import { parseCommand, deniedCommandsToPrefixes } from "../../utils/command-validation"
 import { extractPatternsFromCommand } from "../../utils/command-parser"
 
 interface CommandPattern {
@@ -82,7 +82,10 @@ export const CommandExecution = ({ executionId, text, icon, title }: CommandExec
 	const handleAllowPatternChange = (pattern: string) => {
 		const isAllowed = allowedCommands.includes(pattern)
 		const newAllowed = isAllowed ? allowedCommands.filter((p) => p !== pattern) : [...allowedCommands, pattern]
-		const newDenied = deniedCommands.filter((p) => p !== pattern)
+		const newDenied = deniedCommands.filter((cmd) => {
+			const prefix = typeof cmd === "string" ? cmd : cmd.prefix
+			return prefix !== pattern
+		})
 
 		setAllowedCommands(newAllowed)
 		setDeniedCommands(newDenied)
@@ -91,8 +94,14 @@ export const CommandExecution = ({ executionId, text, icon, title }: CommandExec
 	}
 
 	const handleDenyPatternChange = (pattern: string) => {
-		const isDenied = deniedCommands.includes(pattern)
-		const newDenied = isDenied ? deniedCommands.filter((p) => p !== pattern) : [...deniedCommands, pattern]
+		const deniedPrefixes = deniedCommandsToPrefixes(deniedCommands)
+		const isDenied = deniedPrefixes.includes(pattern)
+		const newDenied = isDenied
+			? deniedCommands.filter((cmd) => {
+					const prefix = typeof cmd === "string" ? cmd : cmd.prefix
+					return prefix !== pattern
+				})
+			: [...deniedCommands, pattern]
 		const newAllowed = allowedCommands.filter((p) => p !== pattern)
 
 		setAllowedCommands(newAllowed)
@@ -194,7 +203,7 @@ export const CommandExecution = ({ executionId, text, icon, title }: CommandExec
 					<CommandPatternSelector
 						patterns={commandPatterns}
 						allowedCommands={allowedCommands}
-						deniedCommands={deniedCommands}
+						deniedCommands={deniedCommandsToPrefixes(deniedCommands)}
 						onAllowPatternChange={handleAllowPatternChange}
 						onDenyPatternChange={handleDenyPatternChange}
 					/>
diff --git a/webview-ui/src/components/settings/AutoApproveSettings.tsx b/webview-ui/src/components/settings/AutoApproveSettings.tsx
index 5ce44c747d..e7eddcdcc7 100644
--- a/webview-ui/src/components/settings/AutoApproveSettings.tsx
+++ b/webview-ui/src/components/settings/AutoApproveSettings.tsx
@@ -5,6 +5,7 @@ import { useAppTranslation } from "@/i18n/TranslationContext"
 import { VSCodeCheckbox } from "@vscode/webview-ui-toolkit/react"
 import { vscode } from "@/utils/vscode"
 import { Button, Input, Slider, StandardTooltip } from "@/components/ui"
+import type { DeniedCommand } from "@roo-code/types"
 
 import { SetCachedStateField } from "./types"
 import { SectionHeader } from "./SectionHeader"
@@ -34,7 +35,7 @@ type AutoApproveSettingsProps = HTMLAttributes<HTMLDivElement> & {
 	allowedCommands?: string[]
 	allowedMaxRequests?: number | undefined
 	allowedMaxCost?: number | undefined
-	deniedCommands?: string[]
+	deniedCommands?: DeniedCommand[]
 	setCachedStateField: SetCachedStateField<
 		| "alwaysAllowReadOnly"
 		| "alwaysAllowReadOnlyOutsideWorkspace"
@@ -84,6 +85,8 @@ export const AutoApproveSettings = ({
 	const { t } = useAppTranslation()
 	const [commandInput, setCommandInput] = useState("")
 	const [deniedCommandInput, setDeniedCommandInput] = useState("")
+	const [deniedCommandMessage, setDeniedCommandMessage] = useState("")
+	const [showCustomMessage, setShowCustomMessage] = useState(false)
 	const { autoApprovalEnabled, setAutoApprovalEnabled } = useExtensionState()
 
 	const toggles = useAutoApprovalToggles()
@@ -104,11 +107,26 @@ export const AutoApproveSettings = ({
 	const handleAddDeniedCommand = () => {
 		const currentCommands = deniedCommands ?? []
 
-		if (deniedCommandInput && !currentCommands.includes(deniedCommandInput)) {
-			const newCommands = [...currentCommands, deniedCommandInput]
-			setCachedStateField("deniedCommands", newCommands)
-			setDeniedCommandInput("")
-			vscode.postMessage({ type: "deniedCommands", commands: newCommands })
+		if (deniedCommandInput) {
+			// Check if this prefix already exists
+			const existingIndex = currentCommands.findIndex(
+				(cmd) => (typeof cmd === "string" ? cmd : cmd.prefix) === deniedCommandInput,
+			)
+
+			if (existingIndex === -1) {
+				// Add new denied command
+				const newCommand: DeniedCommand =
+					showCustomMessage && deniedCommandMessage.trim()
+						? { prefix: deniedCommandInput, message: deniedCommandMessage.trim() }
+						: deniedCommandInput
+
+				const newCommands = [...currentCommands, newCommand]
+				setCachedStateField("deniedCommands", newCommands)
+				setDeniedCommandInput("")
+				setDeniedCommandMessage("")
+				setShowCustomMessage(false)
+				vscode.postMessage({ type: "deniedCommands", commands: newCommands })
+			}
 		}
 	}
 
@@ -356,45 +374,94 @@ export const AutoApproveSettings = ({
 							</div>
 						</div>
 
-						<div className="flex gap-2">
-							<Input
-								value={deniedCommandInput}
-								onChange={(e: any) => setDeniedCommandInput(e.target.value)}
-								onKeyDown={(e: any) => {
-									if (e.key === "Enter") {
-										e.preventDefault()
-										handleAddDeniedCommand()
-									}
-								}}
-								placeholder={t("settings:autoApprove.execute.deniedCommandPlaceholder")}
-								className="grow"
-								data-testid="denied-command-input"
-							/>
-							<Button
-								className="h-8"
-								onClick={handleAddDeniedCommand}
-								data-testid="add-denied-command-button">
-								{t("settings:autoApprove.execute.addButton")}
-							</Button>
+						<div className="space-y-2">
+							<div className="flex gap-2">
+								<Input
+									value={deniedCommandInput}
+									onChange={(e: any) => setDeniedCommandInput(e.target.value)}
+									onKeyDown={(e: any) => {
+										if (e.key === "Enter" && !showCustomMessage) {
+											e.preventDefault()
+											handleAddDeniedCommand()
+										}
+									}}
+									placeholder={t("settings:autoApprove.execute.deniedCommandPlaceholder")}
+									className="grow"
+									data-testid="denied-command-input"
+								/>
+								<Button
+									className="h-8"
+									onClick={handleAddDeniedCommand}
+									data-testid="add-denied-command-button">
+									{t("settings:autoApprove.execute.addButton")}
+								</Button>
+							</div>
+
+							<div className="flex items-center gap-2">
+								<VSCodeCheckbox
+									checked={showCustomMessage}
+									onChange={(e: any) => {
+										setShowCustomMessage(e.target.checked)
+										if (!e.target.checked) {
+											setDeniedCommandMessage("")
+										}
+									}}
+									data-testid="custom-message-checkbox">
+									<span className="text-sm">
+										{t("settings:autoApprove.execute.useCustomMessage")}
+									</span>
+								</VSCodeCheckbox>
+							</div>
+
+							{showCustomMessage && (
+								<Input
+									value={deniedCommandMessage}
+									onChange={(e: any) => setDeniedCommandMessage(e.target.value)}
+									onKeyDown={(e: any) => {
+										if (e.key === "Enter") {
+											e.preventDefault()
+											handleAddDeniedCommand()
+										}
+									}}
+									placeholder={t("settings:autoApprove.execute.customMessagePlaceholder")}
+									className="w-full"
+									data-testid="custom-message-input"
+								/>
+							)}
 						</div>
 
 						<div className="flex flex-wrap gap-2">
-							{(deniedCommands ?? []).map((cmd, index) => (
-								<Button
-									key={index}
-									variant="secondary"
-									data-testid={`remove-denied-command-${index}`}
-									onClick={() => {
-										const newCommands = (deniedCommands ?? []).filter((_, i) => i !== index)
-										setCachedStateField("deniedCommands", newCommands)
-										vscode.postMessage({ type: "deniedCommands", commands: newCommands })
-									}}>
-									<div className="flex flex-row items-center gap-1">
-										<div>{cmd}</div>
-										<X className="text-foreground scale-75" />
-									</div>
-								</Button>
-							))}
+							{(deniedCommands ?? []).map((cmd, index) => {
+								const prefix = typeof cmd === "string" ? cmd : cmd.prefix
+								const hasCustomMessage = typeof cmd === "object" && cmd.message
+
+								return (
+									<StandardTooltip
+										key={index}
+										content={
+											hasCustomMessage
+												? cmd.message
+												: t("settings:autoApprove.execute.defaultDeniedMessage", { prefix })
+										}>
+										<Button
+											variant="secondary"
+											data-testid={`remove-denied-command-${index}`}
+											onClick={() => {
+												const newCommands = (deniedCommands ?? []).filter((_, i) => i !== index)
+												setCachedStateField("deniedCommands", newCommands)
+												vscode.postMessage({ type: "deniedCommands", commands: newCommands })
+											}}>
+											<div className="flex flex-row items-center gap-1">
+												<div>{prefix}</div>
+												{hasCustomMessage && (
+													<span className="text-vscode-descriptionForeground">*</span>
+												)}
+												<X className="text-foreground scale-75" />
+											</div>
+										</Button>
+									</StandardTooltip>
+								)
+							})}
 						</div>
 					</div>
 				)}
diff --git a/webview-ui/src/context/ExtensionStateContext.tsx b/webview-ui/src/context/ExtensionStateContext.tsx
index da7ab63358..616303672e 100644
--- a/webview-ui/src/context/ExtensionStateContext.tsx
+++ b/webview-ui/src/context/ExtensionStateContext.tsx
@@ -7,6 +7,7 @@ import {
 	type ModeConfig,
 	type ExperimentId,
 	type OrganizationAllowList,
+	type DeniedCommand,
 	ORGANIZATION_ALLOW_ALL,
 } from "@roo-code/types"
 
@@ -69,7 +70,7 @@ export interface ExtensionStateContextType extends ExtensionState {
 	setShowRooIgnoredFiles: (value: boolean) => void
 	setShowAnnouncement: (value: boolean) => void
 	setAllowedCommands: (value: string[]) => void
-	setDeniedCommands: (value: string[]) => void
+	setDeniedCommands: (value: DeniedCommand[]) => void
 	setAllowedMaxRequests: (value: number | undefined) => void
 	setAllowedMaxCost: (value: number | undefined) => void
 	setSoundEnabled: (value: boolean) => void
diff --git a/webview-ui/src/i18n/locales/ca/settings.json b/webview-ui/src/i18n/locales/ca/settings.json
index e3f2713ffe..bfdb24f530 100644
--- a/webview-ui/src/i18n/locales/ca/settings.json
+++ b/webview-ui/src/i18n/locales/ca/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Introduïu prefix de comanda (ex. 'git ')",
 			"deniedCommandPlaceholder": "Introduïu prefix de comanda a denegar (ex. 'rm -rf')",
 			"addButton": "Afegir",
-			"autoDenied": "Les comandes amb el prefix `{{prefix}}` han estat prohibides per l'usuari. No eludeixis aquesta restricció executant una altra comanda."
+			"autoDenied": "Les comandes amb el prefix `{{prefix}}` han estat prohibides per l'usuari. No eludeixis aquesta restricció executant una altra comanda.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/de/settings.json b/webview-ui/src/i18n/locales/de/settings.json
index a4a62b8391..4d5a61656f 100644
--- a/webview-ui/src/i18n/locales/de/settings.json
+++ b/webview-ui/src/i18n/locales/de/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Befehlspräfix eingeben (z.B. 'git ')",
 			"deniedCommandPlaceholder": "Befehlspräfix zum Verweigern eingeben (z.B. 'rm -rf')",
 			"addButton": "Hinzufügen",
-			"autoDenied": "Befehle mit dem Präfix `{{prefix}}` wurden vom Benutzer verboten. Umgehe diese Beschränkung nicht durch das Ausführen eines anderen Befehls."
+			"autoDenied": "Befehle mit dem Präfix `{{prefix}}` wurden vom Benutzer verboten. Umgehe diese Beschränkung nicht durch das Ausführen eines anderen Befehls.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/en/settings.json b/webview-ui/src/i18n/locales/en/settings.json
index 6e0f137504..ffb2cd29f3 100644
--- a/webview-ui/src/i18n/locales/en/settings.json
+++ b/webview-ui/src/i18n/locales/en/settings.json
@@ -185,7 +185,11 @@
 			"commandPlaceholder": "Enter command prefix (e.g., 'git ')",
 			"deniedCommandPlaceholder": "Enter command prefix to deny (e.g., 'rm -rf')",
 			"addButton": "Add",
-			"autoDenied": "Commands with the prefix `{{prefix}}` have been forbidden by the user. Do not bypass this restriction by running another command."
+			"autoDenied": "Commands with the prefix `{{prefix}}` have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/es/settings.json b/webview-ui/src/i18n/locales/es/settings.json
index e2db1463af..e7cc0f67a5 100644
--- a/webview-ui/src/i18n/locales/es/settings.json
+++ b/webview-ui/src/i18n/locales/es/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Ingrese prefijo de comando (ej. 'git ')",
 			"deniedCommandPlaceholder": "Ingrese prefijo de comando a denegar (ej. 'rm -rf')",
 			"addButton": "Añadir",
-			"autoDenied": "Los comandos con el prefijo `{{prefix}}` han sido prohibidos por el usuario. No eludes esta restricción ejecutando otro comando."
+			"autoDenied": "Los comandos con el prefijo `{{prefix}}` han sido prohibidos por el usuario. No eludes esta restricción ejecutando otro comando.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/fr/settings.json b/webview-ui/src/i18n/locales/fr/settings.json
index 26018a344b..7f16885f19 100644
--- a/webview-ui/src/i18n/locales/fr/settings.json
+++ b/webview-ui/src/i18n/locales/fr/settings.json
@@ -188,7 +188,11 @@
 			"commandPlaceholder": "Entrez le préfixe de commande (ex. 'git ')",
 			"deniedCommandPlaceholder": "Entrez le préfixe de commande à refuser (ex. 'rm -rf')",
 			"addButton": "Ajouter",
-			"autoDenied": "Les commandes avec le préfixe `{{prefix}}` ont été interdites par l'utilisateur. Ne contourne pas cette restriction en exécutant une autre commande."
+			"autoDenied": "Les commandes avec le préfixe `{{prefix}}` ont été interdites par l'utilisateur. Ne contourne pas cette restriction en exécutant une autre commande.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/hi/settings.json b/webview-ui/src/i18n/locales/hi/settings.json
index 7c8b280427..7a0979e030 100644
--- a/webview-ui/src/i18n/locales/hi/settings.json
+++ b/webview-ui/src/i18n/locales/hi/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "कमांड प्रीफिक्स दर्ज करें (उदा. 'git ')",
 			"deniedCommandPlaceholder": "अस्वीकार करने के लिए कमांड प्रीफिक्स दर्ज करें (उदा. 'rm -rf')",
 			"addButton": "जोड़ें",
-			"autoDenied": "प्रीफिक्स `{{prefix}}` वाले कमांड उपयोगकर्ता द्वारा प्रतिबंधित किए गए हैं। दूसरा कमांड चलाकर इस प्रतिबंध को दरकिनार न करें।"
+			"autoDenied": "प्रीफिक्स `{{prefix}}` वाले कमांड उपयोगकर्ता द्वारा प्रतिबंधित किए गए हैं। दूसरा कमांड चलाकर इस प्रतिबंध को दरकिनार न करें।",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "टूडू",
diff --git a/webview-ui/src/i18n/locales/id/settings.json b/webview-ui/src/i18n/locales/id/settings.json
index b4f9b113b3..da6bfacc77 100644
--- a/webview-ui/src/i18n/locales/id/settings.json
+++ b/webview-ui/src/i18n/locales/id/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Masukkan prefix perintah (misalnya, 'git ')",
 			"deniedCommandPlaceholder": "Masukkan prefix perintah untuk ditolak (misalnya, 'rm -rf')",
 			"addButton": "Tambah",
-			"autoDenied": "Perintah dengan awalan `{{prefix}}` telah dilarang oleh pengguna. Jangan menghindari pembatasan ini dengan menjalankan perintah lain."
+			"autoDenied": "Perintah dengan awalan `{{prefix}}` telah dilarang oleh pengguna. Jangan menghindari pembatasan ini dengan menjalankan perintah lain.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"showMenu": {
 			"label": "Tampilkan menu auto-approve di tampilan chat",
diff --git a/webview-ui/src/i18n/locales/it/settings.json b/webview-ui/src/i18n/locales/it/settings.json
index 82d7b2d041..93b2c30e9f 100644
--- a/webview-ui/src/i18n/locales/it/settings.json
+++ b/webview-ui/src/i18n/locales/it/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Inserisci prefisso comando (es. 'git ')",
 			"deniedCommandPlaceholder": "Inserisci prefisso comando da negare (es. 'rm -rf')",
 			"addButton": "Aggiungi",
-			"autoDenied": "I comandi con il prefisso `{{prefix}}` sono stati vietati dall'utente. Non aggirare questa restrizione eseguendo un altro comando."
+			"autoDenied": "I comandi con il prefisso `{{prefix}}` sono stati vietati dall'utente. Non aggirare questa restrizione eseguendo un altro comando.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/ja/settings.json b/webview-ui/src/i18n/locales/ja/settings.json
index dfa62ab32b..cc2005cf2d 100644
--- a/webview-ui/src/i18n/locales/ja/settings.json
+++ b/webview-ui/src/i18n/locales/ja/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "コマンドプレフィックスを入力（例：'git '）",
 			"deniedCommandPlaceholder": "拒否するコマンドプレフィックスを入力（例：'rm -rf'）",
 			"addButton": "追加",
-			"autoDenied": "プレフィックス `{{prefix}}` を持つコマンドはユーザーによって禁止されています。別のコマンドを実行してこの制限を回避しないでください。"
+			"autoDenied": "プレフィックス `{{prefix}}` を持つコマンドはユーザーによって禁止されています。別のコマンドを実行してこの制限を回避しないでください。",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/ko/settings.json b/webview-ui/src/i18n/locales/ko/settings.json
index 219a5de54a..0e230c41fe 100644
--- a/webview-ui/src/i18n/locales/ko/settings.json
+++ b/webview-ui/src/i18n/locales/ko/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "명령 접두사 입력(예: 'git ')",
 			"deniedCommandPlaceholder": "거부할 명령 접두사 입력(예: 'rm -rf')",
 			"addButton": "추가",
-			"autoDenied": "접두사 `{{prefix}}`를 가진 명령어는 사용자에 의해 금지되었습니다. 다른 명령어를 실행하여 이 제한을 우회하지 마세요."
+			"autoDenied": "접두사 `{{prefix}}`를 가진 명령어는 사용자에 의해 금지되었습니다. 다른 명령어를 실행하여 이 제한을 우회하지 마세요.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/nl/settings.json b/webview-ui/src/i18n/locales/nl/settings.json
index 735339bb66..4a8b267b0b 100644
--- a/webview-ui/src/i18n/locales/nl/settings.json
+++ b/webview-ui/src/i18n/locales/nl/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Voer commando-prefix in (bijv. 'git ')",
 			"deniedCommandPlaceholder": "Voer te weigeren commando-prefix in (bijv. 'rm -rf')",
 			"addButton": "Toevoegen",
-			"autoDenied": "Commando's met het prefix `{{prefix}}` zijn verboden door de gebruiker. Omzeil deze beperking niet door een ander commando uit te voeren."
+			"autoDenied": "Commando's met het prefix `{{prefix}}` zijn verboden door de gebruiker. Omzeil deze beperking niet door een ander commando uit te voeren.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/pl/settings.json b/webview-ui/src/i18n/locales/pl/settings.json
index e25eee34cf..c43200fdca 100644
--- a/webview-ui/src/i18n/locales/pl/settings.json
+++ b/webview-ui/src/i18n/locales/pl/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Wprowadź prefiks polecenia (np. 'git ')",
 			"deniedCommandPlaceholder": "Wprowadź prefiks polecenia do odrzucenia (np. 'rm -rf')",
 			"addButton": "Dodaj",
-			"autoDenied": "Polecenia z prefiksem `{{prefix}}` zostały zabronione przez użytkownika. Nie obchodź tego ograniczenia uruchamiając inne polecenie."
+			"autoDenied": "Polecenia z prefiksem `{{prefix}}` zostały zabronione przez użytkownika. Nie obchodź tego ograniczenia uruchamiając inne polecenie.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/pt-BR/settings.json b/webview-ui/src/i18n/locales/pt-BR/settings.json
index e7243aa6f6..d1d26dccbb 100644
--- a/webview-ui/src/i18n/locales/pt-BR/settings.json
+++ b/webview-ui/src/i18n/locales/pt-BR/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Digite o prefixo do comando (ex. 'git ')",
 			"deniedCommandPlaceholder": "Digite o prefixo do comando para negar (ex. 'rm -rf')",
 			"addButton": "Adicionar",
-			"autoDenied": "Comandos com o prefixo `{{prefix}}` foram proibidos pelo usuário. Não contorne esta restrição executando outro comando."
+			"autoDenied": "Comandos com o prefixo `{{prefix}}` foram proibidos pelo usuário. Não contorne esta restrição executando outro comando.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/ru/settings.json b/webview-ui/src/i18n/locales/ru/settings.json
index 38e986ab88..4df5092723 100644
--- a/webview-ui/src/i18n/locales/ru/settings.json
+++ b/webview-ui/src/i18n/locales/ru/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Введите префикс команды (например, 'git ')",
 			"deniedCommandPlaceholder": "Введите префикс команды для запрета (например, 'rm -rf')",
 			"addButton": "Добавить",
-			"autoDenied": "Команды с префиксом `{{prefix}}` были запрещены пользователем. Не обходи это ограничение, выполняя другую команду."
+			"autoDenied": "Команды с префиксом `{{prefix}}` были запрещены пользователем. Не обходи это ограничение, выполняя другую команду.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/tr/settings.json b/webview-ui/src/i18n/locales/tr/settings.json
index b4b9fd13e4..5ac5694454 100644
--- a/webview-ui/src/i18n/locales/tr/settings.json
+++ b/webview-ui/src/i18n/locales/tr/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Komut öneki girin (örn. 'git ')",
 			"deniedCommandPlaceholder": "Reddetmek için komut öneki girin (örn. 'rm -rf')",
 			"addButton": "Ekle",
-			"autoDenied": "`{{prefix}}` önekli komutlar kullanıcı tarafından yasaklandı. Başka bir komut çalıştırarak bu kısıtlamayı aşma."
+			"autoDenied": "`{{prefix}}` önekli komutlar kullanıcı tarafından yasaklandı. Başka bir komut çalıştırarak bu kısıtlamayı aşma.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/vi/settings.json b/webview-ui/src/i18n/locales/vi/settings.json
index cdae509d5e..d0e17b15ae 100644
--- a/webview-ui/src/i18n/locales/vi/settings.json
+++ b/webview-ui/src/i18n/locales/vi/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "Nhập tiền tố lệnh (ví dụ: 'git ')",
 			"deniedCommandPlaceholder": "Nhập tiền tố lệnh để từ chối (ví dụ: 'rm -rf')",
 			"addButton": "Thêm",
-			"autoDenied": "Các lệnh có tiền tố `{{prefix}}` đã bị người dùng cấm. Đừng vượt qua hạn chế này bằng cách chạy lệnh khác."
+			"autoDenied": "Các lệnh có tiền tố `{{prefix}}` đã bị người dùng cấm. Đừng vượt qua hạn chế này bằng cách chạy lệnh khác.",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "Todo",
diff --git a/webview-ui/src/i18n/locales/zh-CN/settings.json b/webview-ui/src/i18n/locales/zh-CN/settings.json
index aca901cc3e..333d1130a9 100644
--- a/webview-ui/src/i18n/locales/zh-CN/settings.json
+++ b/webview-ui/src/i18n/locales/zh-CN/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "输入命令前缀（例如 'git '）",
 			"deniedCommandPlaceholder": "输入要拒绝的命令前缀（例如 'rm -rf'）",
 			"addButton": "添加",
-			"autoDenied": "前缀为 `{{prefix}}` 的命令已被用户禁止。不要通过运行其他命令来绕过此限制。"
+			"autoDenied": "前缀为 `{{prefix}}` 的命令已被用户禁止。不要通过运行其他命令来绕过此限制。",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "待办",
diff --git a/webview-ui/src/i18n/locales/zh-TW/settings.json b/webview-ui/src/i18n/locales/zh-TW/settings.json
index db3fc3c2cd..72d233b3da 100644
--- a/webview-ui/src/i18n/locales/zh-TW/settings.json
+++ b/webview-ui/src/i18n/locales/zh-TW/settings.json
@@ -187,7 +187,11 @@
 			"commandPlaceholder": "輸入命令前綴（例如 'git '）",
 			"deniedCommandPlaceholder": "輸入要拒絕的命令前綴（例如 'rm -rf'）",
 			"addButton": "新增",
-			"autoDenied": "前綴為 `{{prefix}}` 的命令已被使用者禁止。不要透過執行其他命令來繞過此限制。"
+			"autoDenied": "前綴為 `{{prefix}}` 的命令已被使用者禁止。不要透過執行其他命令來繞過此限制。",
+			"useCustomMessage": "Use custom message",
+			"customMessagePlaceholder": "Enter custom message for this command prefix",
+			"defaultDeniedMessage": "Commands with the prefix '{{prefix}}' have been forbidden by the user. Do not bypass this restriction by running another command.",
+			"hasCustomMessage": "Has custom message"
 		},
 		"updateTodoList": {
 			"label": "待辦",
diff --git a/webview-ui/src/utils/__tests__/command-validation.spec.ts b/webview-ui/src/utils/__tests__/command-validation.spec.ts
index 29370c471f..fbbab96ce2 100644
--- a/webview-ui/src/utils/__tests__/command-validation.spec.ts
+++ b/webview-ui/src/utils/__tests__/command-validation.spec.ts
@@ -12,6 +12,8 @@ import {
 	CommandValidator,
 	createCommandValidator,
 	containsSubshell,
+	findLongestDeniedMatch,
+	deniedCommandsToPrefixes,
 } from "../command-validation"
 
 describe("Command Validation", () => {
@@ -1189,3 +1191,142 @@ describe("Unified Command Decision Functions", () => {
 		})
 	})
 })
+
+describe("Custom Denied Command Messages", () => {
+	describe("deniedCommandsToPrefixes", () => {
+		it("converts string array to prefixes", () => {
+			const result = deniedCommandsToPrefixes(["rm", "sudo", "chmod"])
+			expect(result).toEqual(["rm", "sudo", "chmod"])
+		})
+
+		it("converts DeniedCommand objects to prefixes", () => {
+			const result = deniedCommandsToPrefixes([
+				{ prefix: "rm", message: "Dangerous!" },
+				{ prefix: "sudo" },
+				"chmod",
+			])
+			expect(result).toEqual(["rm", "sudo", "chmod"])
+		})
+
+		it("handles empty array", () => {
+			const result = deniedCommandsToPrefixes([])
+			expect(result).toEqual([])
+		})
+
+		it("handles undefined", () => {
+			const result = deniedCommandsToPrefixes(undefined as any)
+			expect(result).toEqual([])
+		})
+	})
+
+	describe("findLongestDeniedMatch", () => {
+		it("returns null when no match found", () => {
+			const deniedCommands = ["rm", "sudo"]
+			const result = findLongestDeniedMatch("echo hello", deniedCommands)
+			expect(result).toEqual({ prefix: null, message: undefined })
+		})
+
+		it("finds match with string array", () => {
+			const deniedCommands = ["rm", "sudo", "chmod"]
+			const result = findLongestDeniedMatch("rm -rf /", deniedCommands)
+			expect(result).toEqual({ prefix: "rm", message: undefined })
+		})
+
+		it("finds match with DeniedCommand objects", () => {
+			const deniedCommands = [
+				{ prefix: "rm", message: "File deletion is not allowed" },
+				{ prefix: "sudo", message: "Elevated privileges are forbidden" },
+				"chmod",
+			]
+			const result = findLongestDeniedMatch("rm -rf /", deniedCommands)
+			expect(result).toEqual({ prefix: "rm", message: "File deletion is not allowed" })
+		})
+
+		it("returns custom message when available", () => {
+			const deniedCommands = [{ prefix: "sudo", message: "No admin access allowed!" }]
+			const result = findLongestDeniedMatch("sudo apt-get update", deniedCommands)
+			expect(result).toEqual({ prefix: "sudo", message: "No admin access allowed!" })
+		})
+
+		it("returns undefined message for string entries", () => {
+			const deniedCommands = ["sudo"]
+			const result = findLongestDeniedMatch("sudo apt-get update", deniedCommands)
+			expect(result).toEqual({ prefix: "sudo", message: undefined })
+		})
+
+		it("finds longest matching prefix", () => {
+			const deniedCommands = [
+				{ prefix: "git", message: "Git commands restricted" },
+				{ prefix: "git push", message: "Pushing to remote is forbidden" },
+				"git pull",
+			]
+			const result = findLongestDeniedMatch("git push origin main", deniedCommands)
+			expect(result).toEqual({ prefix: "git push", message: "Pushing to remote is forbidden" })
+		})
+
+		it("handles case insensitive matching", () => {
+			const deniedCommands = [{ prefix: "RM", message: "No file deletion" }]
+			const result = findLongestDeniedMatch("rm -rf /", deniedCommands)
+			expect(result).toEqual({ prefix: "rm", message: "No file deletion" })
+		})
+
+		it("handles empty command", () => {
+			const deniedCommands = [{ prefix: "rm" }]
+			const result = findLongestDeniedMatch("", deniedCommands)
+			expect(result).toEqual({ prefix: null, message: undefined })
+		})
+
+		it("handles empty denied commands", () => {
+			const result = findLongestDeniedMatch("rm -rf /", [])
+			expect(result).toEqual({ prefix: null, message: undefined })
+		})
+
+		it("handles undefined denied commands", () => {
+			const result = findLongestDeniedMatch("rm -rf /", undefined as any)
+			expect(result).toEqual({ prefix: null, message: undefined })
+		})
+	})
+
+	describe("Integration with existing functions", () => {
+		it("getCommandDecision works with DeniedCommand objects", () => {
+			const allowedCommands = ["echo", "ls"]
+			const deniedCommands = [{ prefix: "rm", message: "File deletion is dangerous" }, "sudo"]
+
+			// Should auto-deny with custom message available
+			expect(getCommandDecision("rm -rf /", allowedCommands, deniedCommands)).toBe("auto_deny")
+
+			// Should auto-deny without custom message
+			expect(getCommandDecision("sudo apt-get", allowedCommands, deniedCommands)).toBe("auto_deny")
+
+			// Should auto-approve allowed commands
+			expect(getCommandDecision("echo hello", allowedCommands, deniedCommands)).toBe("auto_approve")
+		})
+
+		it("CommandValidator works with DeniedCommand objects", () => {
+			const validator = new CommandValidator(
+				["npm", "echo"],
+				[
+					{ prefix: "rm", message: "Deletion not allowed" },
+					{ prefix: "sudo", message: "Admin access forbidden" },
+					"chmod",
+				],
+			)
+
+			expect(validator.validateCommand("rm file.txt")).toBe("auto_deny")
+			expect(validator.validateCommand("sudo command")).toBe("auto_deny")
+			expect(validator.validateCommand("chmod +x file")).toBe("auto_deny")
+			expect(validator.validateCommand("npm install")).toBe("auto_approve")
+		})
+
+		it("CommandValidator getValidationDetails includes denied command info", () => {
+			const validator = new CommandValidator(["npm"], [{ prefix: "rm", message: "Custom denial message" }])
+
+			const details = validator.getValidationDetails("rm -rf /")
+			expect(details.decision).toBe("auto_deny")
+			expect(details.deniedMatches[0]).toEqual({
+				command: "rm -rf /",
+				match: "rm",
+			})
+		})
+	})
+})
diff --git a/webview-ui/src/utils/command-validation.ts b/webview-ui/src/utils/command-validation.ts
index 700aed554b..aa0c09d700 100644
--- a/webview-ui/src/utils/command-validation.ts
+++ b/webview-ui/src/utils/command-validation.ts
@@ -1,4 +1,5 @@
 import { parse } from "shell-quote"
+import type { DeniedCommand } from "@roo-code/types"
 
 type ShellToken = string | { op: string } | { command: string }
 
@@ -380,6 +381,52 @@ export function findLongestPrefixMatch(command: string, prefixes: string[]): str
 	return longestMatch
 }
 
+/**
+ * Find the longest matching denied command (with optional custom message) from a list of denied commands.
+ *
+ * @param command - The command to match against
+ * @param deniedCommands - List of denied commands (string or object format)
+ * @returns The matching denied command object with prefix and optional message, or null if no match found
+ */
+export function findLongestDeniedMatch(
+	command: string,
+	deniedCommands: DeniedCommand[],
+): { prefix: string | null; message?: string } {
+	if (!command || !deniedCommands?.length) return { prefix: null, message: undefined }
+
+	const trimmedCommand = command.trim().toLowerCase()
+	let longestMatch: { prefix: string; message?: string } | null = null
+
+	for (const denied of deniedCommands) {
+		const prefix = typeof denied === "string" ? denied : denied.prefix
+		const lowerPrefix = prefix.toLowerCase()
+
+		// Handle wildcard "*" - it matches any command
+		if (lowerPrefix === "*" || trimmedCommand.startsWith(lowerPrefix)) {
+			if (!longestMatch || lowerPrefix.length > longestMatch.prefix.length) {
+				longestMatch = {
+					prefix: lowerPrefix,
+					message: typeof denied === "object" ? denied.message : undefined,
+				}
+			}
+		}
+	}
+
+	return longestMatch || { prefix: null, message: undefined }
+}
+
+/**
+ * Convert a list of DeniedCommand objects to a list of prefix strings.
+ * This is used for backward compatibility with existing code.
+ *
+ * @param deniedCommands - List of denied commands (string or object format)
+ * @returns List of prefix strings
+ */
+export function deniedCommandsToPrefixes(deniedCommands: DeniedCommand[]): string[] {
+	if (!deniedCommands) return []
+	return deniedCommands.map((cmd) => (typeof cmd === "string" ? cmd : cmd.prefix))
+}
+
 /**
  * Check if a single command should be auto-approved.
  * Returns true only for commands that explicitly match the allowlist
@@ -508,10 +555,13 @@ export type CommandDecision = "auto_approve" | "auto_deny" | "ask_user"
 export function getCommandDecision(
 	command: string,
 	allowedCommands: string[],
-	deniedCommands?: string[],
+	deniedCommands?: DeniedCommand[],
 ): CommandDecision {
 	if (!command?.trim()) return "auto_approve"
 
+	// Convert DeniedCommand[] to string[] for backward compatibility
+	const deniedPrefixes = deniedCommands ? deniedCommandsToPrefixes(deniedCommands) : undefined
+
 	// Parse into sub-commands (split by &&, ||, ;, |)
 	const subCommands = parseCommand(command)
 
@@ -520,7 +570,7 @@ export function getCommandDecision(
 		// Remove simple PowerShell-like redirections (e.g. 2>&1) before checking
 		const cmdWithoutRedirection = cmd.replace(/\d*>&\d*/, "").trim()
 
-		return getSingleCommandDecision(cmdWithoutRedirection, allowedCommands, deniedCommands)
+		return getSingleCommandDecision(cmdWithoutRedirection, allowedCommands, deniedPrefixes)
 	})
 
 	// If any sub-command is denied, deny the whole command
@@ -622,13 +672,13 @@ export function getSingleCommandDecision(
 export class CommandValidator {
 	constructor(
 		private allowedCommands: string[],
-		private deniedCommands?: string[],
+		private deniedCommands?: DeniedCommand[],
 	) {}
 
 	/**
 	 * Update the command lists used for validation
 	 */
-	updateCommandLists(allowedCommands: string[], deniedCommands?: string[]) {
+	updateCommandLists(allowedCommands: string[], deniedCommands?: DeniedCommand[]) {
 		this.allowedCommands = allowedCommands
 		this.deniedCommands = deniedCommands
 	}
@@ -693,7 +743,10 @@ export class CommandValidator {
 
 		const deniedMatches = subCommands.map((cmd) => ({
 			command: cmd,
-			match: findLongestPrefixMatch(cmd.replace(/\d*>&\d*/, "").trim(), this.deniedCommands || []),
+			match: findLongestPrefixMatch(
+				cmd.replace(/\d*>&\d*/, "").trim(),
+				deniedCommandsToPrefixes(this.deniedCommands || []),
+			),
 		}))
 
 		return {
@@ -741,6 +794,6 @@ export class CommandValidator {
  * Factory function to create a CommandValidator instance
  * This is the recommended way to create validators in the application
  */
-export function createCommandValidator(allowedCommands: string[], deniedCommands?: string[]): CommandValidator {
+export function createCommandValidator(allowedCommands: string[], deniedCommands?: DeniedCommand[]): CommandValidator {
 	return new CommandValidator(allowedCommands, deniedCommands)
 }