If the writ calls for something you don't have such as a recipe, the local merchant for the discipline may have what you need. When I started out doing the daily crafting writs, I would always check those.
You can pre-make all the Alchemy/Provisioning Normal writ requirements and use them on any character.
Here's the lists:
https://en.uesp.net/wiki/Online:Alchemist_Writ
https://en.uesp.net/wiki/Online:Provisioner_Writ