Hi, thanks for the clarification!
You can use %c to insert category in agenda prefix. Calling org-get-category directly is a mistake - the %(...) functions are ran in agenda buffer, not in Org buffer, which `org-get-category' expects.
I used `org-get-category` directly in the example as a minimal case. My actual use case, that I think worked fine before, is to have a function that returns a dynamic prefix based on the entries category (but not necessarily the category itself). Is something like this supported at all?
I now clarified where %(expression) is evaluated in the org-agenda-prefix-format docstring. https://git.savannah.gnu.org/cgit/emacs/org-mode.git/commit/?id=67922b8c0
Appreciated, I thought the eval context was unclear in the docs! ~lou
