Fable usage went up even though I only used Opus

A user on Max 20x, who primarily uses Claude Code with Opus, reported an unexpected increase of over 25 percentage points in their weekly Fable usage. Despite not intentionally using Fable and finding no Fable responses in their local Claude Code logs since September 17, their usage statistics showed a significant rise. The user is inquiring if others have experienced a similar discrepancy.

This report is the first to highlight a potential discrepancy in Claude Code's usage tracking, where Fable usage increased despite the user exclusively using Opus and local logs showing no Fable activity.