what craft skills do i need for a knife build?

[The Concavenator]

im a noob. planing on doing a no psi knife light armor run. but i have no ideas how much points to put in for craft skills. also how bad would it be if i dont have social skills? this is my build idea. any help would be great thx!

https://underrail.info/build/?HgMQCgMDBQYAwqAAwqDCoMKgUAAuACxmZFRUZAAAAAAAAAAkJjE5BlwTEgBOSz5HPMKmFsKz4p2NCuKnvgXfvw

[Zeem]

The stat spread looks pretty good, close to ideal thresholds. Unless you plan to use throwing knives there's no point to maxing out Throwing skill, grenades get max accuracy around 110 effective IIRC. I'd put those leftover points into Hacking or Pickpocket instead. You also overinvested in chem and bio, I'd get some points from them and put in mechanics and electronics instead, as those are the skills used for actually making your primary weapon. You might also throw a couple points at tailoring to help with armor crafting, you'd want a soft-padding infused greater siphoner overcoat with black cloth along with infused greater siphoner tabis to maximize your dodge and evasion.
Base stats are perfect as is, no comment there.
Feats have some glaring omissions. Since knives have trouble getting through armor due to their low base damage I highly recommend getting Expose Weakness ASAP. You'd also want Escape Artist before Depot A, so no later than level 8. You max out Dodge, but you don't make proper use of it with Uncanny Dodge, which is usually the only reason people level Dodge at all.
Here's a rough draft of what I came up with based on your build:
https://underrail.info/build/?HgMQCgMDBQYAMgDCoMKgwqBQUC4ALHBwT0FlAAAAAAAAACQmMU4SBjlcQRMAS0c8wqbCs-KdjQrip74F378

[The Concavenator]

thanks for the info. btw how bad world it be if i drop 2 will and ripper and pick up 2 con and conditioning?

[Zeem]

Knives live and die by crits, and you already have mobility, stealth and dodge/evasion for your defenses. 5 CON is not really enough to tank in light armor either, so it's a bad idea overall. A common rule of thumb is that you don't pick CON between 3 and 7 unless you know exactly what you're doing.

[tymon2701]

Conditioning is quite weak with 5 CON while Ripper crit damage increase is very strong