Second-favorite process (necessary for ISBNs or other URLs): You know it's {{cite book}}, so request a page number when I submit it.

So… add "page" to the recommended list of fields for the template on enwiki?

pages is already "suggested" in the TemplateData.

When you add a template via the citoid service, or when you edit a pre-existing one that does not contain the suggested parameter, the empty-but-suggested parameters are not displayed.

Here's a screenshot of what happens. {{Cite book}} at en.wp has one required and seven suggested parameters. And when you open it, you see a total of four. The four un-used suggested parameters, including pages, are not present.

Got the same remark on it.wiki today.

(As an example, see https://it.wikipedia.org/w/index.php?title=Utente:Elitre_(WMF)/Sandbox&diff=prev&oldid=77448860 . The actual URL I pasted into Citoid was https://books.google.it/books?id=EQ0MAAAAIAAJ&pg=PA61&vq=%22col+grasso,+che+sia+caduto+di+pavone,+o+d%27altri+uccelli,+e+gittalo+sopra+il+pane+fritto+nella+padella+%3B+e%22&source=gbs_quotes_r&cad=6#v=onepage&q&f=false , which does contain the indication of the page.)

Not sure what this is stalled on.

I'm confused about what the complaint is here, so maybe something significant has changed in the past 2.5 years.

The complaint appears to be split into two parts:

1. When I want to add a page to a book citation, it should be displayed without having to click "Add more information".
2. When I put in a citation to a book, it should automatically put in the relevant page number.

I found an ISBN, and used Citoid to add it as a reference. When I edit the citation and scroll down in the dialogue, the pages parameter is there and is quite easily editable, without using "Add more information". Admittedly, it is below the fold, but all the stuff that's above the fold is more important, so there's not much to do about that. So, point 1 seems solved.

The second point is more complex. For some methods of inserting a citation for a book, automatically detecting a page would be impossible; for example, an ISBN is an identifier for the whole book, and by design cannot reference specific pages. It seems this is also the case for a link to Google Books, since there is no page identifier in the URL. What are the other methods of adding a reference to a book that include information about the page number?

In short, this task needs rescoping to be about a specific issue, probably "Add feature to request a page number when adding a citation of a book".

There is a page number identifier in Google Books URLs. Consider https://books.google.com/books?id=eXj7WdwtG3wC&pg=PA319#v=onepage&q&f=false The &pg=PA319 part identifies the page number. It will not always be the page number that's wanted because (1) it's the page number for digital display, which does not always match the physical page number and (2) it's the page number when you opened the book, rather than the page number that you were reading at the time when you copied the URL, but it will be accurate in most cases.

So the request (aka "desired process") is "Copy the 319 out of that URL and pre-paste it into the |pages= field."

So, based on that, some Google Books URLs have page identifiers, but not all of them. Right.

I'm a little wary of autopopulating this, as it might not be the page the user wants, and they might not see it when inserting the reference. It's probably better that a reference be put in without a page number rather than with a page number that's incorrect. A solution to this would need to be figured out.

Isn't that T113262?

In T96000#3788644, @Elitre wrote:

Isn't that T113262?

Yes, it seems so.