Authoring Tests: CodeGen vs. AI Agents

This episode of The Modern .NET Show is supported, in part, by RJJ Software's Strategic Technology Consultation Services. If you're an SME (Small to Medium Enterprise) leader wondering why your technology investments aren't delivering, or you're facing critical decisions about AI, modernization, or team productivity, let's talk.

"It's not just guessing. It's not just saying, "oh, there's something to log in. I think we'll call the button login." It actually knows the button is called Login, it's seen it. So that makes a big difference and makes it much more resilient. So that's definitely a big change, right? It's not just guessing. So definitely you should try it out."— Debbie O'Brien

Hey everyone, and welcome back to The Modern .NET Show; the premier .NET podcast, focusing entirely on the knowledge, tools, and frameworks that all .NET developers should have in their toolbox. I'm your host Jamie Taylor, bringing you conversations with the brightest minds in the .NET ecosystem.

Today, we're joined by Debbie O'Brien to talk about both Playwright and the Playwright MCP server. We started with an introduction to Playwright, and talked about how both it and the MCP server for it can help you to automate both the writing and running of tests for your applications.

Pro tip: If you've been using the Swagger UI in your applications, you've been using Open API.

"And that's where the Playwright MCP comes In because it can automate a browser, it can basically go to the website, it can navigate, it can click, it can hover, it can do everything that you are doing in your tests."— Debbie O'Brien

Along the way, we talked about how Playwright's MCP server can help you to find test cases that you might not have thought of initially. As a perfect example of this while recording this episode, Debbie found a bug in the app that I use to record episodes of the show, and talked about how Playwright MCP would help to recreate and debug the issue.

It's worth pointing out that we recorded this in early August 2025, and that AI quite literally moves very rapidly. Whilst Playwright and MCP servers are not likely to change too much between recording the episode an when it went out, it'll be worth bearing that in mind as we talk about some of the AI stuff.

Before we jump in, a quick reminder: if The Modern .NET Show has become part of your learning journey, please consider supporting us through Patreon or Buy Me A Coffee. Every contribution helps us continue bringing you these in-depth conversations with industry experts. You'll find all the links in the show notes.

Anyway, without further ado, let's sit back, open up a terminal, type in `dotnet new podcast` and we'll dive into the core of Modern .NET.

The full show notes, including links to some of the things we discussed and a full transcription of this episode, can be found at: https://dotnetcore.show/season-8/testing-made-easy-debbie-obrien-explains-playwright-and-its-game-changing-mcp-server

• Playwright
• Jamie's "small" open source project
• Playwright VSCode extension
• Playwright on GitHub
  • Playwright's tests on GitHub... written with Playwright
• Debbie's Movies App website
• GitHub Spark
• Debbie's website
• Debbie on LinkedIn
• Playwright Docs
• Playwright YouTube Channel
• playwright Discord Server
• Supporting the show:
  • Leave a rating or review
  • Buy the show a coffee
  • Become a patron
• Getting in touch:
  • via the contact page
  • joining the Discord
• Podcast editing services provided by Matthew Bliss
• Music created by Mono Memory Music, licensed to RJJ Software for use in The Modern .NET Show
• Editing and post-production services for this episode were provided by MB Podcast Services

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You can support the show by making a monthly donation on the show's Patreon page at: https://www.patreon.com/TheDotNetCorePodcast.

Music created by Mono Memory Music, licensed to RJJ Software for use in The Modern .NET Show.

Editing and post-production services for this episode were provided by MB Podcast Services.