I get the following error when trying to clock into the agenda buffer.
byte-code: Before first headline at position 406 in buffer *Org Agenda* Doesn't matter the location in the agenda buffer. If I go to the org file org-clock-in works fine. Org clock out works fine from the agenda-buffer.
This feature was working before just fine, I didn't add any new packages, or change my init file before it started, but I tried generating the agenda file off two different org files and see the same thing.