Why Testing Matters More Than Ever in Vibe Coding

In this episode, Marcelo welcomes Debbie O’Brien, Microsoft’s Principal Technical Program Manager behind Playwright’s Model Context Protocol (MCP). Together they explore why testing is now more crucial than ever in vibe coding, examining how rigorous testing prevents regressions and builds resilient AI-generated systems. They unpack the full testing spectrum—from unit and integration to E2E, performance, and exploratory tests—and delve into various AI powered tools (include Playwright) that will help you get your testing done quicker and more efficiently through natural-language prompts and agent-powered workflows.

Key Topics Covered

1. Why testing has become essential as vibe coding accelerates development.
2. How unit, integration, E2E, performance, and exploratory tests work together to catch issues early.
3. What Playwright’s Model Context Protocol (MCP) is and how it enables LLMs to control browsers via structured accessibility snapshots.
4. How MCP empowers AI-driven workflows—writing tests in natural language, running them, and autonomously repairing failures.
5. Practical insights from Debbie’s experience on adopting AI testing in real-world teams and reducing brittleness.

Resources to Check Out

• Microsoft Playright