How would you define age here? Last time visited?
I have thought about introducing a way to increase score based on "recentness". There is one problem with the history in general, though: It's quite expensive to load a big browsing history so the plugin will only get a fixed amount of history for a few days back. This is configurable, but I don't think it would scale back as long ago as you're hinting at.
This FF addon [i] uses the dateAdded attribute to sort the bookmarks, I wonder if it's at all relevant/helpful?
[i] https://github.com/heftig/sort-bookmarks/blob/70ffcbfb0cda73...
Last date visited is more complicated. This extension only has it because it merges the results from history API with the bookmarks API. But then it can only go back as far as we fetched the browser history and as far as that exists.
How would you imagine such a query would look like? Right now, the extension only has "search modes" which limit the search results to certain types of entries.
Another beginning might be to just increase score if the item falls within the range in either the bookmark/dateAdded or the history/lastVisited.
This probably covers many useful scenarios e.g. I recall bookmarking (or visiting) a page regarding regex within the last 12mos, so that related item should float to the top.
Note: I haven't played around enough - it might just naturally do this anyway if the order being returned is based on how recent the item is in history or bookmarks!
For bookmark/dateAdded, it might help to display the date added and to allow sorting by it as you suggest. I'm thinking about it.
However, the scope of the extension is rather not being a complete bookmark / history manager replacement. Rather a quick search / navigation tool.
See https://github.com/Fannon/search-bookmarks-history-and-tabs#... (first example, and for more details the options.js).
Regarding the sorting / filtering: I see the value in it, but this would be more work and I want to think it through first. Maybe I'll find the time to add it. If yes, maybe I'll add a "sort" mode that cycles between "score" (default)" "last visited" or "date added". Although only score is available for all types of results.