MediaWiki Documentation Day 2017

The first annual MediaWiki Documentation Day will be held on Friday, May 12th. Help us prepare by listing high priority documentation requests below and volunteering to address documentation requests that you are interested in tackling.

What is the scope of Documentation Day?
Documentation Day is intended to address documentation for any MediaWiki-related software, including APIs, extensions, services, libraries, gadgets, and bot frameworks. Target audiences for documentation include users, wiki administrators, and developers.

What does good documentation look like?
Good documentation should contain seven properties:
 * Clarity - easy to understand
 * Coherence - easy to navigate
 * Completeness - no missing information
 * Concision - no extraneous information
 * Consistency - uses the same terms and concepts throughout
 * Correctness - tested and verified
 * Credibility - Professional, no typos or grammar errors

For code documentation, please refer to the relevant sections of our coding conventions:
 * Manual:Coding conventions
 * Manual:Coding conventions/PHP
 * Manual:Coding conventions/JavaScript

Am I required to participate?
No, anyone can contribute as much or as little documentation as they want, or abstain from Documentation Day entirely.

Requests
Please list any high priority requests below. If possible, include the intended audience and any related Phabricator tasks.

Update on-wiki hooks documentation
From Mainframe98: Update Manual:Hooks and create the missing hooks pages listed at Manual talk:Hooks and Category:Undocumented MediaWiki hooks. It's not a difficult task, since the hooks themselves are listed in hooks.txt in the MediaWiki source code. It's basically copy pasting with the occasional typo/format fixing. The only difficulty here would be figuring out it which version the hooks was added, since that's not clear from hooks.txt.
 * Phab tasks:
 * Volunteers: ?

Consolidate on-wiki Echo developer docs
There are currently 2 different pages of developer documentation for Echo (mainly about how to create new notifications). Some of the documentation overlaps and some of it is outdated. The docs should be updated and consolidated into one page if possible. Kaldari (talk) 18:34, 30 April 2017 (UTC)
 * Existing docs: Notifications/Developer guide, Extension:Echo/Creating a new notification type
 * Phab tasks: ,
 * Volunteers: ?

Results
If there are any results that you want to share, feel free to list them below.