What does this mean?

Whenever I try to use wire text screens, I get this unusual error message,

weapons\gmod_tool\stool.lua:92: attempt to index a nil value

I also get this same message using the measuring stick STool.
I’ve tried updating my wire folders, but to no avail.

If somebody can help me identify this error message, it would be greatly appreciated.

[editline]04:24PM[/editline]

I forgot, it also won’t let me use the Weld tool. I have no idea what to do.

Please help!

[editline]04:36PM[/editline]

Actually nevermind, just a conflicting mod. Lock the thread.