diff --git a/browser_cli/cli.py b/browser_cli/cli.py
index 208b28a..bf38d2b 100755
--- a/browser_cli/cli.py
+++ b/browser_cli/cli.py
@@ -36,6 +36,7 @@ from browser_cli.platform import install_base_dir, is_windows
 console = Console()
 
 NATIVE_HOST_NAME = "com.browsercli.host"
+EXTENSION_ID = "bfpmkhngkjnfhabmfckgeohlilokodkg"
 
 NATIVE_HOST_DIRS = {
     "chrome": {
@@ -284,7 +285,7 @@ def cmd_install(browser):
         wrapper_content = f'@echo off\r\n"{sys.executable}" "{native_host_script_path}" %*\r\n'
         wrapper_path.write_text(wrapper_content, encoding="utf-8")
 
-    # Ask for extension ID
+    # Load extension
     ext_urls = {
         "chrome": "chrome://extensions",
         "chromium": "chrome://extensions",
@@ -297,10 +298,9 @@ def cmd_install(browser):
     console.print(f"  1. Open [cyan]{ext_url}[/cyan]")
     console.print("  2. Enable [bold]Developer mode[/bold] (top-right toggle)")
     console.print(f"  3. Click [bold]Load unpacked[/bold] → select: [cyan]{Path(__file__).parent.parent / 'extension'}[/cyan]")
-    console.print("  4. Copy the [bold]Extension ID[/bold] shown on the extension card\n")
+    console.print(f"  4. Extension ID will be [cyan]{EXTENSION_ID}[/cyan] (fixed by built-in key)\n")
 
-    extension_id = click.prompt("Paste your extension ID here")
-    extension_id = extension_id.strip()
+    extension_id = EXTENSION_ID
 
     # Build native messaging manifest
     manifest = {