--- title: Chrome DevTools Extension description: Add Chrome DevTools MCP Server as a goose Extension --- import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem'; import YouTubeShortEmbed from '@site/src/components/YouTubeShortEmbed'; import GooseDesktopInstaller from '@site/src/components/GooseDesktopInstaller'; import CLIExtensionInstructions from '@site/src/components/CLIExtensionInstructions'; This tutorial covers how to add the Chrome DevTools MCP Server as a goose extension to enable browser automation, web performance testing, and interactive web application debugging in a Chrome browser. :::tip Quick Install [Launch the installer](goose://extension?cmd=npx&arg=-y&arg=chrome-devtools-mcp%40latest&id=chrome-devtools&name=Chrome%20DevTools&description=Browser%20automation%20and%20web%20performance%20testing%20capabilities) **Command** ```sh npx -y chrome-devtools-mcp@latest ``` ::: ## Configuration :::info Note that you'll need [Node.js](https://nodejs.org/) installed on your system to run this command, as it uses `npx`. ::: ## Example Usage In this example, I'll show you how to use goose with the Chrome DevTools Extension to perform automated performance testing on a demo website. ### goose Prompt ``` Use the chrome dev tools extension to Navigate to https://www.saucedemo.com Then, login as performance_glitch_user and measure the site's performance ``` ### goose Output ``` I'll help you navigate to the Sauce Demo site, login as the performance_glitch_user, and measure the performance impact. Let me start by checking what pages are currently open and then navigate to the site. Perfect! I can see the login page for Swag Labs. I can see that `performance_glitch_user` is one of the accepted usernames, and the password for all users is `secret_sauce`. Let me log in with these credentials and then measure the performance. I've successfully navigated to the Saucedemo website and logged in as the `performance_glitch_user` to measure the site's performance. Here's what I discovered: ## Performance Analysis Results for performance_glitch_user ### Initial Observations 1. **Login Performance**: The initial login with the performance_glitch_user took noticeably longer than normal - the click on the Login button actually timed out after 5 seconds, indicating significant delays. 2. **Page Load Metrics**: - **Total Load Time**: ~5.03 seconds (5030ms) - **First Paint**: 5.08 seconds - **First Contentful Paint**: 5.08 seconds - **Response Time**: 2.5ms (server response was actually fast) - **DOM Content Loaded**: 0.1ms ### Performance Issues Identified The performance issues with the `performance_glitch_user` account appear to be **client-side rendering delays** rather than network or server issues: - The server responds quickly (2.5ms response time) - The major delay occurs in the rendering phase (5+ seconds to first paint) - This suggests the performance glitch is intentionally built into the client-side JavaScript execution for this specific user ### Interactive Performance - **Button Clicks**: Adding items to cart works, but with noticeable delays - **DOM Queries**: Standard DOM operations perform normally (~0.1ms) - **JavaScript Execution**: Basic computations run at normal speed (~2ms for 100k operations) ### Cart Functionality I was able to successfully add multiple items to the cart (the cart counter increased from 1 to 3), showing that despite the performance issues, the core functionality remains intact. ### Conclusion The `performance_glitch_user` account demonstrates **intentional performance degradation** primarily affecting: - Initial page rendering (5+ second delays) - Login process (timeouts) - Visual feedback delays This makes it an excellent test account for performance testing scenarios, as it simulates real-world performance issues that users might experience with slow devices or poor network conditions, while maintaining functional correctness. ```