Claude(with MCP) Builds, Runs and Tests Web Apps by Looking At Screenshots now?

Key Concepts

Model Context Protocol (MCP), Claude, Custom GPTs with Actions, File System Access, Browser Automation (Puppeteer), Local vs. Online Services, Code Editing, Marketplace, Mobile Integration, Internet Search, Voice Integration, Diff Editing.

Main Topics and Key Points

Introduction to Claude's Capabilities with MCP Servers

• The video introduces Claude's new ability to interact with local systems using Model Context Protocol (MCP) servers. This allows Claude to read and write files, install dependencies, run applications, and manipulate browsers.
• Example: The presenter demonstrates Claude modifying a JavaScript server file, adding the current date and time, and then verifying the change by taking a screenshot of the running server in a browser.
• Key Point: MCP servers enable Claude to perform tasks autonomously, such as writing code, testing it, and iterating until it works.

Demonstration of Claude's Interaction with a Local Server

• The presenter connects Claude to a local server using a URL and asks it to describe the project.
• Claude requests permission to use tools like "file system list directory" and "read a file." The presenter grants these permissions for the current chat.
• Claude reads the package.json file, identifies the project as a full-stack JavaScript server, and understands its features.
• Claude is then instructed to install and run the server. It requests permission to run commands and reads the output to check for success.
• Example: Claude installs dependencies using npm install, runs the server, and confirms that it's running on port 3000.

Browser Automation with Puppeteer

• Claude is instructed to open a browser and inspect the running server.
• It requests permission to use Puppeteer, a library for browser automation, and to take a screenshot.
• Technical Term: Puppeteer is defined as a library that can manipulate Chrome for browser automation, often used for testing.
• Claude takes a screenshot and accurately identifies the time displayed on the page.
• Claude is then asked to modify the server code to add the current date. It rewrites the file, takes another screenshot, and confirms that the change is visible in the browser.

Setting Up MCP Servers: Official vs. Simplified Method

• The video explains two methods for setting up MCP servers: the official method and a simplified method provided by the presenter.
• Official Method:
  • Requires manually editing the clo desktop config file, located in the user's Library folder (Application Support/cloud).
  • The config file contains JSON entries for each MCP server, including its URL and any required arguments (e.g., allowed folders for file system access).
  • Example: The presenter shows the config file containing entries for the terminal server, file system server, and Puppeteer server.
  • Adding a new server involves adding a new JSON entry with the server's configuration.
• Simplified Method (Presenter's Repo):
  • Involves downloading a repository, opening a terminal in the project folder, and running npm run setup.
  • This script automatically installs dependencies, builds the server, and creates/modifies the clo desktop config file with pre-configured servers.
  • Benefit: Simplifies the setup process, especially for non-technical users.
• Technical Term: npm (Node Package Manager) is used to install dependencies required for the MCP servers.

Windows Compatibility and Caveats

• MCP servers can run on Windows, but with limitations.
• Issue: The presenter encountered issues with Puppeteer failing to load on Windows, preventing browser automation.
• The presenter encourages viewers to share any solutions or insights regarding the Windows Puppeteer issue.
• The setup process on Windows is similar to macOS: download the folder, open the terminal, and run npm run setup.
• The clo desktop config file on Windows is located in AppData\Roaming\clo.

Comparison with Custom GPTs with Actions

• The video compares MCP servers with Custom GPTs with Actions, which also allow chatbots to interact with external services.
• Key Difference: Custom GPTs connect to online services via APIs, while MCP servers connect to local machines.
• Pros and Cons:
  • Custom GPTs work in the browser and on mobile, but have limited access to local files.
  • MCP servers provide access to local files and systems, but require local installation and configuration.
• The presenter mentions a personal project, "chpt server Commander," that attempts to connect GPTs to local files, but notes that it's challenging to set up.

Wish List for Claude and MCP Servers

• The presenter outlines a wish list for future improvements to Claude and MCP servers:
  • Marketplace: A centralized platform for discovering and installing MCP servers with one-click installation and monetization options.
  • Mobile Integration: Extending MCP functionality to mobile devices, potentially by connecting to online services instead of local machines.
  • Internet Search: Improving Claude's internet search capabilities to match or exceed those of GPTs and other search engines.
  • Voice Integration: Adding voice input and output to Claude, similar to GPTs.
  • Diff Editing: Implementing more efficient code editing by only modifying the necessary parts of files instead of rewriting them entirely.
  • Technical Term: Diff editing refers to making minimal changes to a file, only modifying the lines that need to be updated.

Conclusion

• The presenter concludes that MCP servers represent a significant step forward for Claude, enabling it to perform more complex and autonomous tasks.
• The presenter expresses hope that Claude will continue to evolve and incorporate the features on the wish list, potentially becoming a powerful tool for code editing, application development, and more.
• The presenter encourages viewers to share their thoughts and feedback in the comments.