Hi @numbergames You're correct, this is not supported.

I don't have any immediate plans to change the default search response but there's some plans coming together about what v4 will look like, and one of the features I'm pretty sure I will include is a custom field option.

I don't have any plans to integrate append_to_response to the list methods (search, discover, find, etc...) at this time.

Thanks for the quick reply. It's been a lot of fun working with your API. You've clearly put a TON of time into the development.

I've only worked on a few APIs, but one in particular that I like for the custom fields options is Flickr. By default their API doesn't return every URL for every image size option, but you can request one or more sizes (among other optional fields) be included with each search, saving a callback to the image detail endpoint.

Given how much you've done here, you're clearly miles ahead of me on these things, but just thought I'd throw it out there.

Will v4 require the full authentication at all times, or only when querying against private user data? (Would hope for ability to use simple token only where possible.)

I can't say for sure what v4 will look like, only that some of the ideas have been bubbling up ;)

Thanks for the suggestions, I'll definitely consider them where applicable.