You can craft it with a glass bottle, a feather, and an ink sack (The recipe is shapeless). You can also use a glass phial instead of a glass bottle if you so choose.
The Scribing Tools can also be used to provide research theories while working with a Crucible. If you are holding Scribing Tools and Paper, and use a casting wand on a crucible containing a valid combination of Essentia for a recipe that is eligible to research (all prerequisites researched) but not yet unlocked, you will gain the appropriate research notes. This can be very useful when several researches require similar Aspects - for example, to force a particular transmutation recipe to unlock, or to obtain Thaumium without going through all of the metal transmutations. Past the first stage of research (everything that can be researched prior to Unified Thaumic Field Theory), the Crucible is generally only used to feed the Infusion Altar or to make lesser components (such as Nitor for Golem Animation Cores), so opportunities to use scribing tools are greatly reduced.
If you attempt to create something in the Crucible that would have provided you with a theory, but lack Scribing Tools or Paper, you will receive a message informing you that you lacked the means to write down your discovery.