CAOS Debugger

The CAOS Debugger is a Windows program developed by Creature Labs to let you browse running agents, inspect their variables, and step through code as they run. It can also monitor output from DBG: OUTV and DBG: OUTS, and do some other fancy things. Originally intended only for internal use, it has since been released for free, but is somewhat buggy (for instance, dragging the splitter widget crashes it).