Currently the extension recommendations come from 2 sources

• a curated list of extensions mapped to filetypes maintained by the VS Code team.
• the extension list inside the .vscode/extensions.json file in a workspace which is maintained by the workspace owners

A framework that can help explain to the user why and how these recommendations are made is missing

This issue tracks work in improving the extension recommendation system and will span over several iterations.

Things to achieve

• Users should understand why a recommendation is being made. A recommendation can be
  • based on current file type
  • based on current workspace
  • history of types of files opened
• Recommendations should be relevant. For example: User opens a php file long time ago, gets recommendation for a php extension, never again opens a php file. The recommendation continues to show up today. Files/workspaces used more often should influence recommendations than files/workspaces rarely used
• Recommendations list should be short and well sorted as per relevance. For example: the recommendation for current file type and workspace can show up before the ones based on historical usage (moved to September milestone)

We need telemetry in place to

• determine whether recommendations are successful
• assess the success of different ways of presenting recommendations
• associate extensions with features like format/lint/completion/outline etc This can in the future help in recommending by category (moved to September milestone)