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Browser Testing With Devtools

This connects Claude to Chrome DevTools via MCP so it can actually see what's happening in the browser instead of guessing. The agent can grab screenshots, inspect the DOM, read console errors, analyze network requests, and profile performance. Most useful when debugging UI issues or verifying that a fix actually works at runtime. The skill includes a solid security section that's worth reading: it treats all browser content as untrusted data and sets clear boundaries around JavaScript execution. The debugging workflows for UI bugs, network issues, and performance problems are practical and opinionated. Requires the chrome-devtools MCP server configured in your project.

skills.sh installs
67.7K
GitHub stars
114.6K
last updated
Aug 21, 2026

Install

$ npx -y skills add addyosmani/agent-skills --skill browser-testing-with-devtools --agent claude-code

Installs into .claude/skills of the current project.

Files

Browser Testing with DevTools

Overview

Use Chrome DevTools MCP to give your agent eyes into the browser. This bridges the gap between static code analysis and live browser execution — the agent can see what the user sees, inspect the DOM, read console logs, analyze network requests, and capture performance data. Instead of guessing what's happening at runtime, verify it.

When to Use

  • Building or modifying anything that renders in a browser
  • Debugging UI issues (layout, styling, interaction)
  • Diagnosing console errors or warnings
  • Analyzing network requests and API responses
  • Profiling performance (Core Web Vitals, paint timing, layout shifts)
  • Verifying that a fix actually works in the browser
  • Automated UI testing through the agent

When NOT to use: Backend-only changes, CLI tools, or code that doesn't run in a browser.

Setting Up Chrome DevTools MCP

Installation

Add the following to your project's .mcp.json or Claude Code settings:

{
  "mcpServers": {
    "chrome-devtools": {
      "command": "npx",
      "args": ["-y", "chrome-devtools-mcp@latest", "--isolated"]
    }
  }
}

Sponsors

Details

Repository
github.com/addyosmani/agent-skills
Categories
Frontend Development, Backend & APIs, Testing & QA, AI & Agent Building, Debugging, Automation & Workflows, Design & UI/UX
First seen
Apr 16, 2026

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