Interdepedence is the name of the game. Sure, you can survive on your own fairly well, but at a risk. If you're by yourself, I would recommend making extra tools and storing them. Also, it is important to remember that even if you start with tools and play by yourself, you won't necessarily be able to craft all the tools you need to do the things you want. There is always a chance you may need to trade with another player.
If I were playing solo and got all my tools taken, I would forage or gather some resources and then offer them up to other players for tools. Or, I would simply go to a "good" aligned tribal village and ask. Chances are they'll give you what they can spare.
Anyway, I think the game should allow players to form small (2-6 player tribes) and allow players to build camps solo. But, in the end, Xsyon is a game about player interdependence, which isn't to be confused with depedence.
If a new character get killed and looted of all tools, is there a way to survive and get some new tools without other players help?
Some tips for you.
Don't carry your crafting tools with you unless you need them when you venture out, Like a logging axe. But no reason for you to carry crafting tools for leather crafting when your out killing animals. Yes you will need your hunting knife, but losing just a single item is better then losing all of them.
So if you don't have any storage bings etc. to store stuff in after you get into game. (during or right at launch) You better find someone that would be willing to create you one.