Peter Thomas enhanced secret detection in the coder/trivy repository by implementing minimum-length validation for private keys, addressing the challenge of false positives from short or example strings. He used Go and regular expressions to refine the detection logic, ensuring only meaningful-sized keys were flagged as secrets. To maintain reliability, Peter expanded the automated test suite, adding targeted tests that validated the new minimum-length criteria and safeguarded against regression. His work focused on improving detection accuracy while minimizing performance impact, demonstrating a thoughtful approach to balancing precision and efficiency in secret scanning. The project emphasized robust testing and careful validation throughout development.