ToolKit is a version of UTIL which contains a number of tools to help you build and debug Prolog programs. The ones which are currently provided are helper -- help utility & try_hard_to_see pp -- pretty-printer ixref -- interactive cross-referencer count -- clause counter vcheck -- variable check Other tools exist : medic -- for mode-checking in interpreted code timing -- for obtaining call counts modgen -- Chris Mellish's mode generator but are not currently loaded. TELL [400,422] about bugs in these tools or ideas for new ones.