Quote from lahearn2018 >>

what should be written for adding darkvision to a homebrew speices

 
Nothing. Snippets do not add things to species. 

You would need the Modifier in the Species homebrew tool (type: sense, subtype: darkvision, fixed value: the distance in ft). The snippet would just be text.

Quote from ImaBeeJkImaWasp >>

Solved it. Counterintuitively, wrapping the expression in parentheses was the issue. Here is the functioning snippet: {{4+(classlevel/5)@max:1,rounddown*2+(classlevel/11)@max:1,rounddown*2+(classlevel/17)@max:1,rounddown*2}}

I've explored this a bit. From this comment:

Why does a nested parenthesis work here, but not in the solution for comment #3? It might be related to how the snippet modifiers are implemented. This example has @min and #unsigned outside of the nested parenthesis, but my first try in comment #3 had the @max and @rounddown on the inside some nested parenthesis before applying the next bit of math. Maybe the snippet modifiers can't be inside a set of parenthesis when applying later calculations. Knowing this could be useful when building snippets.

I'm trying to make a subclass right now, and I have the pet's stats under an action as a snippet. How would I add text at certain levels?

Quote from HamburgerWithCheese593 >>

I'm trying to make a subclass right now, and I have the pet's stats under an action as a snippet. How would I add text at certain levels?

I don't believe there is a way to dynamically change the snippet text the way you're wanting.

Do these snippet codes work in homebrewed magic item descriptions? I want to have the description show the actual intelligence spell save DC, without having to look elsewhere.

But when I tried (DC {{savedc:int}}) it did not show properly,  instead just showing the text of the snippet code.

Snippet codes only work in the Snippet code box not in Description boxes.

{{scalevalue}} still isn't working for me in Class Feature Options. Has anyone else got it to work?

Edit: Nevermind, appears to be working now!

I'm trying to make a gauntlet item for one of my players that gives +1 AC and a 1d6 + Strength modifier Slashing Unarmed Strike that can follow up a weapon attack and apply disadvantage to the target's next attack roll on a hit. The AC bonus is going to be tied to a magic item being equipped and unequipped, and the attack is an action granted by a feat. Is there any way to apply the Light and Sap properties to the attack, or will that just have to be a note in the description?