[BUG] API Error: Usage credits required for 1M context

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?

I am receiving an error when using Claude Code: API Error: Usage credits required for 1M context · run /usage-credits to turn them on, or /model to switch to standard context

What Should Happen?

Expected behavior:
The standard context window should work without usage credits for Pro subscribers (which I am).

Actual behavior:
The error persists even after /model reports the model was successfully changed to Sonnet 4.6. Restarting the session does not help.

Additional context:

~/.claude/settings.json contains only {"theme": "light"} — no 1M context flag is set
No API key is used; auth is via Claude Pro subscription

Error Messages/Logs

❯ r u ok?
API Error: Usage credits required for 1M context · run /usage-credits to turn them on, or /model to switch to standard context

✻ Worked for 0s

❯ claude --version
API Error: Usage credits required for 1M context · run /usage-credits to turn them on, or /model to switch to standard context

Steps to Reproduce

Steps to reproduce:

Open Claude Code
Receive error: API Error: Usage credits required for 1M context
Run /model → switch to Sonnet 4.6 (default)
Send any message
Same error appears again immediately

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

API Error: Usage credits required for 1M context · run /usage-credits to turn them on, or /model to switch to standard context

Platform

Other

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_