diff --git a/src/core/Cline.ts b/src/core/Cline.ts
index b5deecc463..1d9aa7189e 100644
--- a/src/core/Cline.ts
+++ b/src/core/Cline.ts
@@ -1,7 +1,8 @@
 import { Anthropic } from "@anthropic-ai/sdk"
+import { loadClineIgnoreFile } from "../utils/cline-ignore"
 import cloneDeep from "clone-deep"
 import { DiffStrategy, getDiffStrategy, UnifiedDiffStrategy } from "./diff/DiffStrategy"
-import { validateToolUse, isToolAllowedForMode, ToolName } from "./mode-validator"
+import { isToolAllowedForMode, ToolName } from "./mode-validator"
 import delay from "delay"
 import fs from "fs/promises"
 import os from "os"
@@ -76,6 +77,7 @@ export class Cline {
 	private urlContentFetcher: UrlContentFetcher
 	private browserSession: BrowserSession
 	private didEditFile: boolean = false
+	private ignoreContent: string = ""
 	customInstructions?: string
 	diffStrategy?: DiffStrategy
 	diffEnabled: boolean = false
@@ -132,6 +134,9 @@ export class Cline {
 		this.providerRef = new WeakRef(provider)
 		this.diffViewProvider = new DiffViewProvider(cwd)
 
+		// Load ignore content once at initialization
+		loadClineIgnoreFile(cwd).then((content) => (this.ignoreContent = content))
+
 		if (historyItem) {
 			this.taskId = historyItem.id
 		}
@@ -1149,15 +1154,17 @@ export class Cline {
 					const { mode } = (await this.providerRef.deref()?.getState()) ?? {}
 					const { customModes } = (await this.providerRef.deref()?.getState()) ?? {}
 					try {
-						validateToolUse(
+						const isAllowed = isToolAllowedForMode(
 							block.name as ToolName,
 							mode ?? defaultModeSlug,
 							customModes ?? [],
-							{
-								apply_diff: this.diffEnabled,
-							},
+							{ apply_diff: this.diffEnabled },
 							block.params,
+							this.ignoreContent,
 						)
+						if (!isAllowed) {
+							throw new Error(`Tool "${block.name}" is not allowed in ${mode ?? defaultModeSlug} mode.`)
+						}
 					} catch (error) {
 						this.consecutiveMistakeCount++
 						pushToolResult(formatResponse.toolError(error.message))
@@ -2718,9 +2725,7 @@ export class Cline {
 
 		// Add warning if not in code mode
 		if (
-			!isToolAllowedForMode("write_to_file", currentMode, customModes ?? [], {
-				apply_diff: this.diffEnabled,
-			}) &&
+			!isToolAllowedForMode("write_to_file", currentMode, customModes ?? [], { apply_diff: this.diffEnabled }) &&
 			!isToolAllowedForMode("apply_diff", currentMode, customModes ?? [], { apply_diff: this.diffEnabled })
 		) {
 			const currentModeName = getModeBySlug(currentMode, customModes)?.name ?? currentMode
diff --git a/src/shared/__tests__/modes.test.ts b/src/shared/__tests__/modes.test.ts
index ac9d1a5f7e..41747ad087 100644
--- a/src/shared/__tests__/modes.test.ts
+++ b/src/shared/__tests__/modes.test.ts
@@ -1,4 +1,4 @@
-import { isToolAllowedForMode, FileRestrictionError, ModeConfig } from "../modes"
+import { isToolAllowedForMode, FileRestrictionError, IgnoredFileError, ModeConfig } from "../modes"
 
 describe("isToolAllowedForMode", () => {
 	const customModes: ModeConfig[] = [
@@ -186,3 +186,47 @@ describe("FileRestrictionError", () => {
 		expect(error.name).toBe("FileRestrictionError")
 	})
 })
+
+describe("IgnoredFileError", () => {
+	it("formats error message correctly", () => {
+		const error = new IgnoredFileError("test.js")
+		expect(error.message).toBe("File test.js is ignored by .clineignore")
+		expect(error.name).toBe("IgnoredFileError")
+	})
+})
+
+describe("clineignore handling", () => {
+	const ignoreContent = "*.js\n!important.js\nnode_modules/"
+
+	it("throws IgnoredFileError for ignored files in read group", () => {
+		expect(() =>
+			isToolAllowedForMode("read_file", "code", [], undefined, { path: "test.js" }, ignoreContent),
+		).toThrow(IgnoredFileError)
+
+		expect(() =>
+			isToolAllowedForMode("read_file", "code", [], undefined, { path: "node_modules/test.ts" }, ignoreContent),
+		).toThrow(IgnoredFileError)
+	})
+
+	it("throws IgnoredFileError for ignored files in edit group", () => {
+		expect(() =>
+			isToolAllowedForMode("write_to_file", "code", [], undefined, { path: "test.js" }, ignoreContent),
+		).toThrow(IgnoredFileError)
+
+		expect(() =>
+			isToolAllowedForMode("apply_diff", "code", [], undefined, { path: "node_modules/test.ts" }, ignoreContent),
+		).toThrow(IgnoredFileError)
+	})
+
+	it("allows non-ignored files", () => {
+		expect(isToolAllowedForMode("read_file", "code", [], undefined, { path: "test.ts" }, ignoreContent)).toBe(true)
+
+		expect(
+			isToolAllowedForMode("write_to_file", "code", [], undefined, { path: "important.js" }, ignoreContent),
+		).toBe(true)
+	})
+
+	it("allows tools without paths", () => {
+		expect(isToolAllowedForMode("browser_action", "code", [], undefined, undefined, ignoreContent)).toBe(true)
+	})
+})
diff --git a/src/shared/modes.ts b/src/shared/modes.ts
index c29800c5b5..0aea69983f 100644
--- a/src/shared/modes.ts
+++ b/src/shared/modes.ts
@@ -1,4 +1,5 @@
 import { TOOL_GROUPS, ToolGroup, ALWAYS_AVAILABLE_TOOLS } from "./tool-groups"
+const { shouldIgnorePath } = require("../utils/cline-ignore")
 
 // Mode types
 export type Mode = string
@@ -154,12 +155,31 @@ export class FileRestrictionError extends Error {
 	}
 }
 
+// Custom error class for ignored files
+export class IgnoredFileError extends Error {
+	constructor(filePath: string) {
+		super(`File ${filePath} is ignored by .clineignore`)
+		this.name = "IgnoredFileError"
+	}
+}
+
+/**
+ * Checks if a tool is allowed for a given mode, including .clineignore restrictions
+ * @param tool The tool name to check
+ * @param modeSlug The mode slug to check against
+ * @param customModes Array of custom mode configurations
+ * @param toolRequirements Optional map of tool-specific requirements
+ * @param toolParams Optional parameters passed to the tool
+ * @param ignoreContent Optional .clineignore file content
+ * @returns true if tool is allowed, throws error otherwise
+ */
 export function isToolAllowedForMode(
 	tool: string,
 	modeSlug: string,
 	customModes: ModeConfig[],
 	toolRequirements?: Record<string, boolean>,
-	toolParams?: Record<string, any>, // All tool parameters
+	toolParams?: Record<string, any>,
+	ignoreContent?: string,
 ): boolean {
 	// Always allow these tools
 	if (ALWAYS_AVAILABLE_TOOLS.includes(tool as any)) {
@@ -188,6 +208,16 @@ export function isToolAllowedForMode(
 			continue
 		}
 
+		// Check .clineignore for read/edit groups
+		if (
+			toolParams?.path &&
+			ignoreContent &&
+			(groupName === "read" || groupName === "edit") &&
+			shouldIgnorePath(toolParams.path, ignoreContent)
+		) {
+			throw new IgnoredFileError(toolParams.path)
+		}
+
 		// If there are no options, allow the tool
 		if (!options) {
 			return true