Not really, aside from the obvious like paddle and lifejacket. I’ve been fishing off a Fish and Dive with nothing other than a seat and two rod holders for the last three years. Have you seen the CKFC forum on the fishing.net.nz site?
Like grimace said, you do not really need much, but its easy to have a lot on a Kayak. .
A life Jacket with pockets is a great help to keep things ornganised. A couple of lashes to tie down the rods are quite important. The normal fishing gear (hooks, sinkers, pliers ect), a bright colour flag or hat for safety.
I am also greatly interested in Kayak fishing. But I am not very good at riding one those. Where can I get more information on this, as I would like to try it. I have never tried it as I do not have much information on it and I find it very difficult to ride a Kayak. Thank you!!