[BUG] Desktop app shows "Out of extra usage" and disables input despite 91% weekly / 61% extra usage remaining

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

OS: Windows 11 Pro 10.0.26200
App version: Claude Code v2.1.108
Plan: Claude Max (5x)
Exact error: "Out of extra usage" banner at bottom of chat, input box is completely disabled (cannot type)

Usage at time of bug:

• Current session: 4% used
• Weekly All models: 91% used (resets in 17hr)
• Sonnet only: 5% used
• Extra usage: $303.04 / $500 (61% used), balance $49.99, auto-reload on

Key evidence this is a bug, not a real limit:

1. Claude Code CLI (terminal) works perfectly fine on the same account at the same time
2. Weekly usage is only 91%, not 100%
3. Extra usage has $197 remaining budget and $49.99 balance
4. Creating a new session in the desktop app also shows the same error — input is disabled across ALL sessions, not just the one that hit "Prompt is too long"

Sequence of events:

1. Was using desktop app normally in a long session
2. One session hit "API Error: Prompt is too long" (context grew too large)
3. After that error, the app started showing "Out of extra usage" on that session
4. Tried opening a new session — same "Out of extra usage", cannot type
5. Rebooted the entire PC — same issue persists
6. Claude Code CLI works fine on the same account simultaneously

This appears to be a UI state bug where the "Prompt is too long" API error incorrectly triggers the "Out of extra usage" lockout state, and that state persists across all sessions including new ones, even after a full reboot.

What Should Happen?

1. "Prompt is too long" should NOT trigger "Out of extra usage" — these are different errors
2. Even if one session's context is too large, new sessions should work normally
3. The input box should never be disabled when the user has remaining usage quota

Error Messages/Logs

API Error: Prompt is too long
⚡ Out of extra usage [Upgrade]

Steps to Reproduce

1. Use Claude Desktop app on Max (5x) plan with extra usage enabled
2. Have a very long conversation until "Prompt is too long" API error appears
3. Observe that the input box becomes disabled with "Out of extra usage"
4. Try creating a new session — input is still disabled
5. Reboot PC — issue persists
6. Verify Claude Code CLI works fine on the same account

Claude Model

Sonnet 4.6 / High

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.108

Platform

Claude Max

Operating System

Windows 11 Pro

Terminal/Shell

N/A (Desktop app issue)

Additional Information

Related issues: #51442, #50237, #46812 — similar symptoms but different root cause. Those report "Usage limit reached" while this specifically traces the trigger to a "Prompt is too long" error corrupting the usage state across all sessions.