I created my first homebrew magic item… does someone have suggestions on what to improve?

So, for a campaign I had in mind, I wanted a wizard student npc to have a way of quickly traveling up to the castle, where his old wizard teacher sat. But searching through teleportation spells, they all required quite a high spellcasting level. So I had the idea of creating a magic item, that could be used instead- Arcane Chalk. 

Here’s the link to it:

https://www.dndbeyond.com/magic-items/11846854-arcane-chalk

I wanted to ask if anyone had any feedback on it? I think it turned out quite well. 

It's a really cool concept, but the description is WAY too wordy. You can simplify it to this:

This stick of pale blue chalk has 6 charges. While holding the chalk, you can expend one charge to cast the spell Teleportation Circle or Dimension Door.

Oh, that sums it up pretty well. Thank you! :D