This section describes commands specific to the debugger. In the debugger, you can also do anything that you can do in the top-level loop including evaluation of forms and the standard listener commands.
Upon entry to the debugger the implicit current stack frame is set to the top of the execution stack. The debugger commands allow you to move around the stack, to examine the current frame, and to leave the debugger. The commands are all keywords, and as such case-insensitive, but are shown here in lower case for clarity.
You can get brief help listing these commands by entering
at the debugger prompt.
LispWorks User Guide and Reference Manual - 21 Dec 2011