Your AI agent fixed the bug, but what else did it change?

Source: Trail of Bits · OCT 21, 2026

Today we’re publishing patching-bugs and regression-hunt , two plugins that let engineers delegate patch development and regression checks to agents. Our patching-bugs plugin reproduces reported bugs, develops fixes, and tests them. The regression-hunt plugin checks whether any changes break previously working and supported behavior. Engineers can direct the work and review their results; maintainers can supply their own security assumptions and patching requirements, so the agents work within the project’s rules. We built patching-bugs and regression-hunt through Patch the Planet , our joint initiative with OpenAI, where we’ve co-authored hundreds of security patches for widely used open-source projects. Motivated by our major successes on projects like Scapy , our plugins draw on our analysis of merged patches and thousands of our engineers’ Codex sessions. The plugins provide maintainers with a structured workflow, evidence, independent checks, and best practices to improve their pa