
Bug Squad is an IBM Bob-powered debugging pipeline designed to take a bug ticket from initial report to a reviewed and tested fix while answering an important question: what else could this change break? The system divides debugging into four specialized Bob subagents: Reproducer, Investigator, Fixer, and Reviewer. The Reproducer converts the bug ticket, logs, and specification into a failing test that proves the issue. The Investigator identifies the root cause and runs a pre-fix Blast Radius analysis. The Fixer patches the code until the tests pass. Finally, the Reviewer performs a post-fix Blast Radius check and prepares the pull-request description. The key feature is Blast Radius, our change-impact analyzer. A Python AST/tree-sitter scanner builds a call and dependency graph of the codebase. Bob then reasons over that graph to determine which dependencies represent meaningful risks. Rather than simply reporting that one function calls another, Bob can identify behavioral assumptions, such as a caller depending on an existing return type or behavior. Impacted components are classified as High, Medium, or Low risk with an explanation and information about test coverage. After the fix, the graph is generated again so the before-and-after results can highlight possible new regressions. For validation, Bug Squad uses an original sample application with deliberately seeded bugs and can also use closed issues and known fix commits from permissively licensed open-source repositories. These real fixes provide ground truth for comparing Blast Radius predictions with what maintainers actually changed. A lightweight dashboard is designed to show metrics such as time saved, tests added, and Blast Radius precision and recall. Bug Squad combines deterministic static analysis with Bob's contextual reasoning. Instead of using AI only to generate a patch, we use Bob throughout a structured engineering workflow: reproduce the problem, investigate its cause, implement the fix, test it, review it, and understand its wider impact.
27 Sep 2026