I'm currently in the early stages of developing an Emacs major mode for the Stack Exchange Network (see this question if you're interested in helping at the moment).

I'm a little torn on how to set up the use of the API within the mode.

First off, I want to ask if there is a way to download preliminary data en masse just as email clients will download email headers. In Emacs (and other environments, I'd assume), it's preferable to make as few network requests as practically possible, and I'd further like to not waste my user's API request limits. A simple yay/nay will suffice, I can have fun playing with the API until I find a winner, but I don't want such a search to last forever.

Secondly, I need to know if I need to keep the API key secret or not. If I do, I'm not sure how I'm going to effect its protection, as Emacs Lisp files are stored in plain text (and byte-compiled files should be easy to reverse-engineer, possibly as simple as byte-decompile-file, if such exists). Obviously, I want to avoid the key I was given for the mode to be abused by one and then suspended for everyone. (By API Key limit 10k is Per IP Address or Globally?, I'm assuming that the key will not drain globally for each individual use (per IP), but I can't assume the same principle holds for abuse.)

I am fairly new to StackApps and am not familiar with the tags and their use.
Those with the power: feel free to change them as you will.

I'm currently in the early stages of developing an Emacs major mode for the Stack Exchange Network. I'm a little torn on how to set up the use of the API within the mode.

Is there a way to download preliminary data en masse just as email clients will download email headers? In Emacs (and other environments, I'd assume), it's preferable to make as few network requests as practically possible, and I'd further like to not waste my user's API request limits.