diff --git a/.changeset/lemon-pots-tell.md b/.changeset/lemon-pots-tell.md
new file mode 100644
index 000000000..0c075469f
--- /dev/null
+++ b/.changeset/lemon-pots-tell.md
@@ -0,0 +1,5 @@
+---
+"claude-dev": minor
+---
+
+added IS_TEST build flag
diff --git a/.vscode/launch.json b/.vscode/launch.json
index c03c771a6..e87e2ad7c 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -16,6 +16,19 @@
 				"IS_DEV": "true",
 				"DEV_WORKSPACE_FOLDER": "${workspaceFolder}"
 			}
+		},
+		{
+			"name": "Run Extension (Test Mode)",
+			"type": "extensionHost",
+			"request": "launch",
+			"args": ["--extensionDevelopmentPath=${workspaceFolder}"],
+			"outFiles": ["${workspaceFolder}/dist/**/*.js"],
+			"preLaunchTask": "${defaultBuildTask}",
+			"env": {
+				"IS_DEV": "true",
+				"IS_TEST": "true",
+				"DEV_WORKSPACE_FOLDER": "${workspaceFolder}"
+			}
 		}
 	]
 }
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
index 84ebaf3d0..16b95dbbf 100644
--- a/.vscode/tasks.json
+++ b/.vscode/tasks.json
@@ -14,6 +14,14 @@
 				"isDefault": true
 			}
 		},
+		{
+			"label": "watch:test",
+			"dependsOn": ["npm: build:webview:test", "npm: dev:webview", "npm: watch:tsc", "npm: watch:esbuild:test"],
+			"presentation": {
+				"reveal": "never"
+			},
+			"group": "build"
+		},
 		{
 			"type": "npm",
 			"script": "build:webview",
@@ -32,6 +40,25 @@
 				}
 			}
 		},
+		{
+			"type": "npm",
+			"script": "build:webview:test",
+			"group": "build",
+			"problemMatcher": [],
+			"isBackground": true,
+			"label": "npm: build:webview:test",
+			"presentation": {
+				"group": "watch",
+				"reveal": "never",
+				"close": true
+			},
+			"options": {
+				"env": {
+					"IS_DEV": "true",
+					"IS_TEST": "true"
+				}
+			}
+		},
 		{
 			"type": "npm",
 			"script": "dev:webview",
@@ -77,6 +104,30 @@
 				"group": "watch",
 				"reveal": "never",
 				"close": true
+			},
+			"options": {
+				"env": {
+					"IS_DEV": "true"
+				}
+			}
+		},
+		{
+			"type": "npm",
+			"script": "watch:esbuild:test",
+			"group": "build",
+			"problemMatcher": "$esbuild-watch",
+			"isBackground": true,
+			"label": "npm: watch:esbuild:test",
+			"presentation": {
+				"group": "watch",
+				"reveal": "never",
+				"close": true
+			},
+			"options": {
+				"env": {
+					"IS_DEV": "true",
+					"IS_TEST": "true"
+				}
 			}
 		},
 		{
diff --git a/esbuild.js b/esbuild.js
index 9ca34fd59..4504046e1 100644
--- a/esbuild.js
+++ b/esbuild.js
@@ -4,6 +4,7 @@ const path = require("path")
 
 const production = process.argv.includes("--production")
 const watch = process.argv.includes("--watch")
+const test = process.env.IS_TEST === "true"
 
 /**
  * @type {import('esbuild').Plugin}
@@ -68,6 +69,10 @@ const extensionConfig = {
 	minify: production,
 	sourcemap: !production,
 	logLevel: "silent",
+	define: {
+		"process.env.IS_DEV": JSON.stringify(!production),
+		"process.env.IS_TEST": JSON.stringify(test),
+	},
 	plugins: [
 		copyWasmFiles,
 		/* add to the end of plugins array */
diff --git a/package.json b/package.json
index a30a340f8..c711fcee9 100644
--- a/package.json
+++ b/package.json
@@ -302,8 +302,12 @@
 		"compile": "npm run check-types && npm run lint && node esbuild.js",
 		"watch": "npm-run-all -p watch:*",
 		"watch:esbuild": "node esbuild.js --watch",
+		"watch:esbuild:test": "IS_TEST=true node esbuild.js --watch",
 		"watch:tsc": "tsc --noEmit --watch --project tsconfig.json",
 		"package": "npm run build:webview && npm run check-types && npm run lint && node esbuild.js --production",
+		"package:test": "IS_TEST=true npm run build:webview:test && npm run check-types && npm run lint && IS_TEST=true node esbuild.js --production",
+		"build:webview:test": "cd webview-ui && IS_TEST=true npm run build",
+		"watch:test": "IS_TEST=true npm-run-all -p watch:tsc watch:esbuild:test",
 		"compile-tests": "tsc -p ./tsconfig.test.json --outDir out",
 		"watch-tests": "tsc -p . -w --outDir out",
 		"pretest": "npm run compile-tests && npm run compile && npm run lint",
diff --git a/src/extension.ts b/src/extension.ts
index ed22d984d..211223507 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -33,6 +33,7 @@ export function activate(context: vscode.ExtensionContext) {
 	const sidebarWebview = new WebviewProvider(context, outputChannel)
 
 	vscode.commands.executeCommand("setContext", "cline.isDevMode", IS_DEV && IS_DEV === "true")
+	vscode.commands.executeCommand("setContext", "cline.isTestMode", IS_TEST && IS_TEST === "true")
 
 	context.subscriptions.push(
 		vscode.window.registerWebviewViewProvider(WebviewProvider.sideBarId, sidebarWebview, {
@@ -408,7 +409,7 @@ export function deactivate() {
 //
 // This is a workaround to reload the extension when the source code changes
 // since vscode doesn't support hot reload for extensions
-const { IS_DEV, DEV_WORKSPACE_FOLDER } = process.env
+const { IS_DEV, DEV_WORKSPACE_FOLDER, IS_TEST } = process.env
 
 if (IS_DEV && IS_DEV !== "false") {
 	assert(DEV_WORKSPACE_FOLDER, "DEV_WORKSPACE_FOLDER must be set in development")
diff --git a/webview-ui/package.json b/webview-ui/package.json
index 9bde60e61..ed7132125 100644
--- a/webview-ui/package.json
+++ b/webview-ui/package.json
@@ -6,6 +6,7 @@
 	"scripts": {
 		"dev": "vite",
 		"build": "tsc -b && vite build",
+		"build:test": "tsc -b && vite build",
 		"preview": "vite preview",
 		"lint": "eslint .",
 		"test": "vitest run",
diff --git a/webview-ui/vite.config.ts b/webview-ui/vite.config.ts
index fd31daa87..01d34eb43 100644
--- a/webview-ui/vite.config.ts
+++ b/webview-ui/vite.config.ts
@@ -44,6 +44,7 @@ export default defineConfig({
 		"process.env": {
 			NODE_ENV: JSON.stringify(process.env.IS_DEV ? "development" : "production"),
 			IS_DEV: JSON.stringify(process.env.IS_DEV),
+			IS_TEST: JSON.stringify(process.env.IS_TEST),
 		},
 	},
 	resolve: {