Org-roam and Org-mode custom properties

As a newbie I am a bit confused regarding Org-mode properties and I would like to understand what exactly can I use in the capture templates that I am trying to set up.

Org-mode manual specifically defines property as “a key-value pair associated with an entry”, which means user can define its own custom properties.

My question is: Are custom properties allowed in Org-roam as well? (I read Org-roam manual but I still don’t know the answer to this question).

And if I can set up my own custom properties, is it possible to query custom property?

I think it is possible to show custom properties when you do org-roam-node-find by customizing org-roam-node-display-template. Thanks to @nobiot I could show tags with this code:

(setq org-roam-node-display-template (concat "${title:*} " (propertize "${tags:30}" 'face 'org-tag)))

see the manual entry. As described in the manual, the number after tags, is the size of the string shown, and * to include everything I think can be used only once and it is already in the title. The propertize part is to show a different face from title.

Otherwise, I think whatever works for org-mode works also for org-roam.

Thank you!

Do you know where you can get a list of the available fields to use with this beyond property and tags?

Org-roam is designed to let you “customize your own”. Have a look at the wiki entries from here onward; there are a couple of examples.