One of the biggest hidden pains of building products with AI coding agents is regression testing.
A new feature written by an agent can quietly break existing functionality and wipe out days of effort. I’ve run into this multiple times.
The problem isn’t feature velocity. It’s stability.
My solution: use structured Skills for testing and documentation.
First, a quick primer.
Test cases are foundational to the Software Development Life Cycle (SDLC). Well-written test cases can often replace complex feature or requirement documents.
Once code is written, you typically perform:
1. Unit testing — validates the functionality of a single module or feature
2. Integration testing — ensures different modules work correctly together.
3.Regression testing — confirms that new changes haven’t broken existing functionality.
In many early-stage products, most of this testing is manual. Let’s assume a simple CI/CD pipeline and manual test execution for this discussion.
Here’s how I use Skills:
For large features, I create a detailed, phase-wise plan. After each phase, structured test cases are generated and stored alongside the plan. Test execution logs are maintained in the same file.
But the real leverage comes later.
In one example, I was building a dashboard for AI Personas so users could track what their agents were doing while they focused on other work. All test cases and execution logs were captured during development.
On subsequent iterations, coding agents extract the full test history and automatically generate a regression checklist. Because execution logs already exist, the agent can focus on real historical breakpoints instead of hallucinating edge cases.
You can go further:
Add an impact analysis step inside the Skill to prioritize affected requirements.
Log every PR and commit automatically.
Maintain structured change history for easier rollback.