I can't find a way to reset to defaults the tools options, I wonder if it is possible, something similar to the brush settings but that can be applied to the each tool parameters. I tend to forget what I moved previously and then I have no idea what was there previously, Thank you for any comments.

If you are interested in resetting the tool options and parameters, they are stored in the krita.rc file.

If you are on linux, they should be here (starting in your home directory)
.kde/share/apps/krita/kritarc

that files saves a lot of miscellaneous preferences like tool settings. We currently don't have a button for that on the user interface. I don't believe there is anything in the application to do that.

Thank you for the info scottpetrovic, I was hoping for a "on the fly" short cut or button. not a deal breaker though, I guess I would have to live with it,