I have this hook in my init.el to prevent CIDER and Eglot from conflicting
(defun +cider-disable ()
"Disable some CIDER integrations, as they are provided by the LSP."
(remove-hook 'completion-at-point-functions #'cider-complete-at-point t)
(remove-hook 'eldoc-documentation-functions #'cider-eldoc t))
(add-hook 'cider-mode-hook #'+cider-disable)
But it would be nice to have customization options cider-use-eldoc cider-use-cap to control that, similar to how cider-use-xref already works.The main reason that there's a cider-use-xref option is that without it one has to mess with the keybindings (as some commands in CIDER predate the existence of xref in Emacs). Generally for the completion functions and similar I think it's better to just use the standard Emacs mechanisms to configure those if needed.
Btw, for Eldoc we've had a configuration option for ages:
(setq cider-eldoc-display-for-symbol-at-point nil)I'm not opposed to add a config about the completion as well, but I think this won't improve much the user experience as still you'll probably need to change the value for it in some hooks.
Probably we need some dedicated section in the manual for the interplay with Eglot. Something similar to https://emacs-lsp.github.io/lsp-mode/tutorials/clojure-guide/ that @ericdallo created in the past for lsp-mode.