Systems, methods, apparatus and software can be implemented to provide a debugger agent, either separate form or integrated into the script-based testing platform, to coordinate the selection, activation, and or/operation of debuggers suitable for a particular unit and program under test. Such a debugger agent can provide run time monitoring and debugging activities where previously not possible. The debugger agent is generally independent agent, in that it can work with a variety of types of test scripts, test script handlers, programming languages, and debuggers without customization. Moreover, implementation generally needs no code instrumentation.