Okay, so occasionally I need to look up a MediaWiki message key. I go to api.php (e.g., https://meta.wikimedia.org/w/api.php) and allmessages is no longer there. There used to be a link directly to allmessages. :-(
I don't think if I ask for an allmessages link back that it'll happen, but I also think that discovery of query submodules (e.g., list=allmessages or list=allcategories) isn't great. I don't think users will know to look under a generic term like "query" to find this information and that seems like a real workflow issue that we should explore.
One idea I had was making the single page option more prominent. Currently you need to scroll down the page to find the "single page" option. You can try searching the page text for it, but every time I do, I expect "single page" and I've forgotten that it's listed as "all help in one page". So I try a quick text search, fail, and then scroll down the page and I click https://meta.wikimedia.org/w/api.php?action=help&recursivesubmodules=1, and then search for "allmessages" on the page before finally reaching https://meta.wikimedia.org/w/api.php?action=query&meta=allmessages.
Can we add a more prominent "single page" link to api.php? For example: "This is an auto-generated MediaWiki API documentation page." --> "This is an auto-generated MediaWiki API documentation page (view as single page)." where the parenthetical is linked to the recursivesubmodules=1 page.