consult-hoogle uses wraps the functionality of Haskell search engine and integrates it with the Emacs completion system with the help of consult.
Use M-x consult-hoogle to begin a hoogle search. The resulting interface looks like this:
By default it shows the documentation of the selected candidate in a separate window. The documentation window can be turned by calling consult-hoogle with a prefix arg. Where the documentation window appears can be configured by adding an entry to display-buffer-alist for " *Hoogle Documentation*".
If you are using vertico along with extensions, then using vertico-buffer-mode, the candidates and the documentation window can be arranged to appear side by side.
This will likely require configuring display-buffer-alist for "*vertico-buffer*" as well as " *Hoogle Documentation*". Using vertico-buffer-mode only for this command can be done using vertico-multiform-mode.