I can confirm what Fefa is saying. 

I tried it and i crafted 10 flint shovel heads, i damaged few and did perfect the other few. The heads stacked either way and the 10 of them counted as "perfect". I can also confirm that when you have Item Rarity Mod, the rarity is calculated after the craft of the tool, which causes this mod to give the bonus as if the item had no rarity Creating pieces of epic+ quality to start "damaged" rather than getting a 25% to the overall durability. But besides that, it does not cause crash or anything. It only means that item durability and this mod calculate durability at different stages. 

Hopefully both authors come together to create a compatibility patch where Rarity gets the 25% bonus too :) that would make both mods a musst have for most people hehehehe

Nyarc Thanks for the Update!

@DonaldRTS

1.3.1 has introduced this bug, and i missed it in testing, as its fixed in 1.4.0, I will bring out 1.3.2 as a Hotfix quickly! 

Nyarc

I am using Version 1.3.1 and when completing a stone tool with a bunch of mistakes, it is treated as if I had done it Perfectly.

here is what my Chat log Looked like:

25.3.2026 19:01:09 [Chat] [Precision Knapping] 2 mistake(s)! 3 remaining (100% durability) @ 0
25.3.2026 19:01:12 [Chat] [Precision Knapping] 2 mistake(s)! 1 remaining (47% durability) @ 0
25.3.2026 19:01:17 [Chat] [Precision Knapping] Completed with 4 mistake(s) - 47% durability @ 0
25.3.2026 19:01:17 [Chat] [Precision Knapping] Perfect! +50% bonus durability @ 0

Notice how I had 4 mistakes total, which meant that I should have had only 47% durability. However, in the exact same tick, I got another message that said it was perfect, making the Durability of the Tool 150%.

@Narg this should not happen.
Specifically build a algorithm that detects spots like this that are impossible to do without fracturing, and marks them as safe to delete. - But you are correct.
The other error was an oversight i did never test, when that spot in the middle is hit, it wont finish the craft automatically, thats fixed now.  Ty!
1.3.1 soon

Nyarc was just trying to make flint arrowheads with precision mode and ran into 2 errors. First, the arrowheads pattern has one part to be removed fully enclosed by the kept arrowheads, so there's no way to remove it without getting a fracture, I was lucky twice to have the fracture take out only the unnecessary bits, but lost 2 more flint to immediate 2 errors. Also, sometimes I would knap it correctly, but after finishing the arrowheads would just stay on the ground and not complete the craft.

Brilliant idea for a mod, I always thought knapping was too easy, fast, and straightforward compared to clay molding, but didn't know what could be done to fix it. The edge-enforcement mode is perfect. This will help my immersion a lot.

Knapster's evil twin. Really interesting mod, good job, gonna have to test it out!

Helo, crafted tools dont compare with in game tutorial steps because game not see this items like vanilla tools, can you fix this ?

Anybody feel free to Contribute to the Project on Github if you want to if you have Coding Knowledge and can help make the Charged Strikes come to fruition!

@EnderMelody
Thanks for the feedback!
Yeah the Charged Strike is just some small feature im testing out, im grateful for that feedback. That is beyond my knowledge capabilities though, and i dont want to halfass that mechanic without proper Guidelines / UI Overlay to show whats happening.

EnderMelody yea i feel charged strike has potential to be a lot more satisfying and rewarding, but it's pretty lame by itself.

i feel like the charged strike mode could be made more interesting. if you dont mind my input, itd be cool if you could add a tool mode or something similar to knapping that allowed you to select charged mode instead of it being config set only. you could then have the normal mode work as vanilla, and have charged mode allow you to break lots of parts off with one hit. im thinking something similar to the fracture system (weve been using this on my server and i absolutely love it. once you learn how it works a bit it becomes a good risk/reward system for speed vs precision) where you would select the voxel to hit, charge up your hit, move to the direction you want to fracture in, and then release to destroy a lot of voxels in a cone quickly but with a bit of randomness to it. itd be a cool way to have a more controlled mass knap system with its own risk/reward (and be more realistic). love the mod btw!

Galena Thank you, has been fixed now in 1.3.0

Compatibility with Toolsmith has an issue:

When you knap a whetstone, precise knapping gives a bonus amount instead of additional durability.

Topminator 
You are right, its not the best design, i will make a seperate config option for this

Edit: Done

Narg actually that sounds pretty nice

1.21.5 tools don't get the buff without advanced mode. i don't know if that's intended

Nyarc not non-voxel, just not locked to one recipe. Like if you want to make an axe, but chip off to much, just chip it into a knife shape instead and make a knife.

Narg What do you mean by this? Non Voxel based? Out of my scope.

VoiCat 
I tested it, its compatible. Only Toolheads crafted with this get a custom Attribute, and it carries over to the new Tool System from Toolsmith.

 
Edit: Thoroughly tested, Flint tools cant be crafted with any other Tool Handle anyway - and my custom Durability Modifier still carries over to "Head Durability".
The durability modifier transfers because both mods use the same durability attribute

Nyarc so I'm not entirely sure if it isn't, but Toolsmith is one of those mods that add their own entire systems to the game, so it's basically the Butchering situation to use another mod as an example: Precision Knapping might work with Toolsmith, but it wouldn't surprise me if it didn't. It's not gonna crash the game, because rather than removing the vanilla method of toolmaking, its system is an in-game alternative to it that's just better (though more tedious since you "physically" put the tools together rather than crafting them in the grid and there's the whole sharpness and wear systems, but again, it's all worth it).

Either way, the way the best tools are made is to combine a tool handle with a grip with smithed toolhead (a cast toolhead is worse in the sense of having vanilla durability) and a binding. Their combined durability is the resulting tool's durability value, which is where I'm unsure about the compatibility: the changed value from this mod might register, but it might also not, I could just be paranoid, but honestly either way I do think you could benefit (at the very least inspiration-wise for further features?) from taking a look at that mod since I think it's very cool and also the philosophy of reusing and reforging one good tool instead of making far too many copies that break far too quickly is good for realism.

Sorry for yapping about another mod in your thread xd

Also ty for letting me know in terms of both points.

Love the idea of this mod. On a similar note, how hard would it be to make freeform knapping you think?

VoiCat
Can you tell me what part of Toolsmith would be Incompatible? I have never played with it myself.

Adding Durability was my plan honestly. Will be done, but needs more thorough patching on adding more Durability for the Tools, i need a smart solution for that.

The "not perfect shape" example you did is already kind of implemented, just use Advanced Mode , or just higher MistakeCount in general.

I love the concept behind this mod, but I have shaky hands, so idk if I'll actually enjoy it 😔

I'll try it anyway, but yeah.

Not sure whether you'd be interested in making anything like that, but it would be cool if somehow being more precise with knapping gave durability bonuses to the final tool.

The idea is closer in spirit to the Toolsmith mod (on which topic, a compatibility with that mod would be great), but yeah would be nice if the mod not just punished but also offered rewards of some kind for doing a good job, plus I feel like it's somewhat realistic too: a stone axe does not need to have a perfect shape but obviously one of better make is gonna perform better.

Might be interesting to have it so random bits near the edge are missing so every chunk of flint isn't identical. to keep it workign with stacks of flint you could pregen 256 possible shapes and then each stack keeps a list of which variants it contains and randomly pulls from that when placing.

Thanks for the comments.

Reizeron
You are right, this is more intended for more experienced players when knapping gets too trivial.
Will release source on github then shortly on next release.

Venusgate
thats is a great idea actually. Not entirely sure how the best way of implementation - some Parts might be critical when breaking, some others only might lower Tools durability - you are right.
I could manually define this for each recipe, but it couldnt dynamically patch other mods like this.

I was literally wishing for a mod like this - thank you!

Funny. The exact same thing was patched out in 1.4.4.1.

Given how easy it was (is) to screw up knapping irl and how abundant knapping resources are in the game, I think this mod seems perfectly balanced and realistic as it is. Maybe not for the new players though, I think the reason devs didn't add a failure option to the knapping system was to gradually ease the players into the voxel minigames - knapping is easy, clayforming is a bit more complex (can waste materials), smithing is even harder (can royally screw up). Nonetheless, great idea!

And yes, I'd appreciate the source code, I hope it could help me learn how to make harmony patches myself.

+1 on more forgiving version of this. Maybe you still get tool head with missing voxels, but with diminished max durability; and on precision finish, +25% over vanilla durability? 

Your mod, tho o7

pretty cool idea for realism, if you end up changing the interactions maybe it'd be cool if you had some kind of skill involved that would improve the quality of the tool, not sure if its in your interest though