zhooks
zhooks is a tool for displaying the code for all Zsh hook functions (such as precmd), as well as the contents of hook arrays (such as precmd_functions). It is useful in debugging conflicts between interactive scripts.

Installation:
Simply source zhooks from your .zshrc:
source /path/to/zhooks.plugin.zsh
or load it using your favorite Zsh plugin manager or framework. Then run the command zhooks from the command line to see a thorough report.
zhooks returns true when hooks are being used and false when they are not.
Zsh Hooks Functions and Hook Arrays
Zsh has the hook functions:
chpwdperiodicprecmdpreexeczshaddhistoryzsh_directory_namezshexit
The corresponding arrays have _functions appended to their names:
chpwd_functionsperiodic_functionsprecmd_functionspreexec_functionszshaddhistory_functionszsh_directory_name_functionszshexit_functions