No notification when Opus usage exhausted and model falls back to Sonnet

Problem

When approaching the weekly Opus usage limit, Claude Code shows warning notifications. However, when the limit is actually hit and the system silently falls back to Sonnet, there is no notification or indicator.

This means:

• /model still shows "Opus" as the selected model, even though Sonnet is being served
• /usage shows 100% but there's no proactive alert
• Users can unknowingly work on complex tasks expecting Opus-quality responses while getting Sonnet

Expected behavior

A clear notification when the model fallback actually occurs, such as:

• A one-time message: "Opus usage limit reached — responses are now served by Sonnet until weekly reset"
• The status line or /model output reflecting the actual model being served, not just the preference
• A visual indicator (e.g. the model name in the status bar changing or showing a downgrade icon)

Current behavior

• Warnings appear before hitting the limit
• No notification when the limit is hit
• /model continues to show Opus as if nothing changed
• Users only discover the downgrade by checking /usage and inferring

Impact

Users may waste time on complex architectural work or subtle debugging expecting Opus reasoning, not realizing they're getting Sonnet. Conversely, they might pause work unnecessarily if they knew they were on Sonnet and could switch to simpler tasks.

---

🤖 Generated with Claude Code