AI Driven E2E Testing with the Theia IDE

Manual testing takes time. Writing end-to-end tests takes even more. What if you could automatically test your web app by simply talking to an AI agent?

Now you can-with the App Tester Agent in the AI-powered Theia IDE, built on Theia AI.

🎥 Watch the full demo:

Test Any Web App-No Test Code Required

In this short video demo, we demonstrate the App Tester Agent, a new AI assistant in Theia IDE that allows you to run fully autonomous, end-to-end tests of your web applications. The agent interacts with your app as a real user would-clicking buttons, filling forms, evaluating results-and reports back with detailed findings.

Here’s how it works:

• Launch your app (e.g. via the Coder agent)
• Ask the App Tester to validate it (e.g. “Test my calculator app, focus on multiplication”)
• The agent:
  • Opens a browser via the integrated Playwright MCP Server
  • Creates and executes test cases autonomously
  • Verifies expected vs actual results
  • Detects bugs and produces reproducible reports

No test code. No manual setup. Just prompt and play.

Inject a Bug, Let the Agent Catch It

To showcase the power of the agent in the demonstration, we first introduce a bug using Theia’s Coder Agent: it replaces a multiplication with a division in the app logic. Once deployed, the App Tester spots the error immediately-highlighting wrong results, providing diagnostic output, and suggesting what went wrong.

And to close the loop? We feed the report back to the Coder Agent, which automatically locates and fixes the bug-completing a powerful prompt → test → fix cycle.

Powered by Theia AI and MCP

The App Tester Agent uses Theia AI under the hood and integrates with the Model Context Protocol (MCP) to control a browser through Playwright. This design makes it:

• Fully extensible to your own project setup
• Capable of understanding and using custom prompts
• Able to incorporate domain-specific usage instructions for more reliable testing

Want to test an app that requires login? A complex form wizard? A real-time dashboard? Just adjust the agent’s prompt or embed project-specific guides.

Try the App Tester Today

🧪 Use the App Tester Agent in the AI-powered Theia IDE
📺 Watch the demo above to see it in action
🧰 Learn more about Theia AI

Build Your Own AI-Powered Testing Tools

At EclipseSource, we help teams bring AI into their development workflows-from coding to testing, from IDEs to engineering tools. Whether you’re building a custom testing agent, adapting Theia IDE to your stack, or exploring AI-native workflows-we’re here to help.

👉 Services for Building AI-enhanced Tools and IDEs
👉 Support for AI-Native Software Engineering
👉 Contact us to bring AI autonomy into your development process