workspace.google.com
In short: Google Workspace Marketplace (workspace.google.com) accepts public workspace app listing. It is free to submit, takes a moderate amount of preparation, and scores 98/100 on our impact ranking (highest impact).
Build an your tool add-on for Drive, Docs, Sheets, Gmail, or another Workspace product and publish it.
Must genuinely integrate with Google Workspace and pass OAuth, configuration, and app review.
Priority is do first, which sets the band. It is free and moderate to complete, which adjusts it within that band. The score ranks your queue — it is not a measure of domain authority.