org-finalize-agenda-hook

org-finalize-agenda-hook is a variable defined in `org-agenda.el'.
Its value is

nil

• This variable is an alias for `org-agenda-finalize-hook'.
• This variable is obsolete since 24.3;
  use `org-agenda-finalize-hook' instead.
• This variable may be risky if used as a file-local variable.

Documentation:
Hook run just before displaying an agenda buffer.
The buffer is still writable when the hook is called.

You can modify some of the buffer substrings but you should be
extra careful not to modify the text properties of the agenda
headlines as the agenda display heavily relies on them.

You can customize this variable.