View custom org agendas without first storing in org-agenda-custom-commands?

Question

What is the preferred method of building (viewing) a custom agenda without modifying org-agenda-custom-commands? I am hoping that there is a function like org-agenda-list or org-todo-list that accepts a custom agenda command definition like those that would be added to `org-agenda-custom-commands.

Edit: Essentially just bypassing the org-agenda dispatcher / stored custom commands

An example taken from the org-mode manual:

(setq org-agenda-custom-commands
  '(("O" "Office block agenda"
     ((agenda "" ((org-agenda-ndays 1)))
      (tags-todo "+PRIORITY=\"A\"")
      (tags-todo "computer|office|phone")
      (tags "project+CATEGORY=\"elephants\"")
      (tags "review" ((org-agenda-files '("~/org/circuspeanuts.org"))))
      (todo "WAITING"))
     ((org-agenda-compact-blocks t)))

I think that org-agenda concatenates the results of individual sub-commands (like org-tags-view) internally. What I'm looking to do is skip the traditional org-agenda dispatcher and construct the agenda directly from an arbitrary definition like (from the above):

'((agenda "" ((org-agenda-ndays 1)))
  (tags-todo "+PRIORITY=\"A\"")
  (tags-todo "computer|office|phone")
  (tags "project+CATEGORY=\"elephants\"")
  (tags "review" ((org-agenda-files '("~/org/circuspeanuts.org"))))
  (todo "WAITING"))
 ((org-agenda-compact-blocks t)))

The key being that the definition is subject only to the constraints for org-agenda-custom-commands. It could simply be a tags agenda or a multipart one like that shown.

I originally thought that the user-defined function type that can be added to org-agenda-custom-commands might be the trick, but it looks like it's treated as a match predicate (it's not really mentioned in the documentation).

I'm asking because I'd like to view an agenda that has a dynamically-generated definition.

Answer 1

Depending on exactly what kind of agenda you're trying to build, org-tags-view may do what you want:

(org-tags-view &optional TODO-ONLY MATCH)

Show all headlines for all ‘org-agenda-files’ matching a TAGS criterion. The prefix arg TODO-ONLY limits the search to TODO entries.

This basically what a tags or tags-todo type entry in org-agenda-custom-commands does. The rest of the custom command definition is just variable/value pairs that are let bound when you call org-tags-view. For example,

(let ((org-agenda-overriding-header "Test"))
  (org-tags-view nil "+test"))

will find anything labeled test and set the title of the agenda to "Test". Any other org-agneda-* variable can be set similarly.