To edit guides, you must be signed in - and using game account(s) that prove you own at least 10 games. Editing options will then be enabled automatically.
You can't. Games - and their achievements - can only be added by a user (e.g. you) who owns the game signing in with Steam or Xbox and syncing your achievement progress. This will make the game - and its achievements - appear automatically.
You can then add guide info to the game itself and to the achievements.
This is coming soon(tm)!
Descriptions for hidden achievements are not retrievable over the Steam API, so this is not present where a game's only source of achievement data is Steam. If we also have the game tracked on Xbox, the descriptions will be sourced from there.
Yeah, we'd love to! But we can't unless the network themselves provide an API. Otherwise its against their terms of service to scrape their site for your profile/achievement data. We like playing their games too so would really rather not be banned!
Ofc feel free to get in touch with Origin/Google/Ubi/etc to ask them to publish APIs for user profile and achievement data, that'd be great...
Yeah, you need it to not be private...