This task is an attempt to gather all the pieces that would be useful for creating an ecosystem of creating, storing and displaying alt text for images. It focuses on Wikimedia wikis but most if it should be applicable for any MediaWiki.

Authoring alt text

• Make it easy to add alt text with UploadWizard
• Make an external tool for mass-authoring alt text for existing files
• Make a MediaWiki feature or external tool for translating alt text
• Copy existing inline alt-text to Commons?
• Use Growth suggested edits (on Commons): T325015: Suggested task: Describe images with alt text
• In Growth "add image" tasks: T296820: Support adding alternative text in add image workflow

Storing alt text

• On Wikimedia wikis, the obvious way to store alt text is structured data on Commons.
  • The temporary solution is T166094: Allow editors to provide default alt text on Wikimedia Commons file description pages.
  • The more correct eventual solution (blocked on Wikidata development) is T328634: Use a multilingual Wikibase property for storing alt text on Commons.
• A simple method for storing alt text on non-Wikibase wikis: T21906: Allow default alternate text for images to be provided on the file description page
• An abstraction layer so the client doesn't have to care about the storage method: T328638: Provide an API for accessing alt text (and possibly other structured data) stored with MediaWiki file uploads
• Another abstraction layer for foreign images (e.g. using a Commons image on Wikipedia): T328639: Allow access to (some) structured image metadata across wikis

Displaying alt text

• As a default in thumbnails/galleries
• On the file description page
  • In schema.org metadata?
• In generated lists (categories, lists of new files)
• In image search: T287106: Determine the best source of alt text for MediaSearch image results
• In interfaces which use PageImage:
  • article search: T320299: [S] Special:Search images should not have links without alt text for their contents
  • article cards in apps?
• In MediaViewer wikitext and HTML embed code snippets
• Dynamic interfaces (e.g. MediaViewer, hovercards): is that useful for accessibility?
  • Special:Homepage: T322319: Use commons image caption as alt text for article images
• Maybe offer as default in editing tools:
  • WikiEditor
  • VisualEditor

There is T213585: Images (on articles, on file/category pages, and in the media viewer) should default to use their structured data alt text when available - it should probably be split up to more narrowly scoped tasks.

Other

• Index alt text so that it is taken into account when searching for images.
• Metrics: T289443: Gather data on use of image alt text on Wikimedia wikis