[BUG] Pro: "Usage credits required for 1M context" despite credits enabled — Sonnet 4.6 [1m] forced to 200K after Fable 5 suspension

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?

On the Pro plan, my Claude Code context window dropped from 1M to 200K after the Claude Fable 5 / Mythos 5 suspension on June 12, 2026.

When the model is set to sonnet[1m], every request fails with:
"API Error: Usage credits required for 1M context · turn on usage credits at claude.ai/settings/usage, or use --model to switch to standard context"

This is incorrect — usage credits ARE enabled and have a balance.

Evidence this is a backend flag/sync bug, not a real credit or quota issue:

• Usage credits: ENABLED, $0.00 of $40.00 used (Settings → Usage)
• Plan limits nearly empty: 5-hour limit 29%, Weekly (all models) 3%
• Fresh session with only ~36K tokens — not a bloated session
• Model explicitly set to sonnet[1m], yet /context shows 36.1k / 200.0k (18%) instead of /1000k
• Before the Fable 5 suspension, 1M worked for days (context reached 540K+, impossible under a real 200K cap)
• .claude.json contains "cachedExtraUsageDisabledReason": "out_of_credits" — a stale cached value not updated after enabling usage credits

What Should Happen?

With usage credits enabled and a credit balance available ($0 of $40 used), Sonnet 4.6 should provide the full 1M context window on Claude Code (per support.claude.com/en/articles/8606394). /context should show X / 1000k, not X / 200.0k.

Error Messages/Logs

API Error: Usage credits required for 1M context · turn on usage credits at claude.ai/settings/usage, or use --model to switch to standard context

Steps to Reproduce

1. Be on the Pro plan (billingType: apple_subscription) with usage credits enabled ($0 of $40 used)
2. Start a fresh Claude Code session (Claude Desktop on macOS)
3. Set the model to sonnet[1m]
4. Send any message
5. Result: request rejected with "Usage credits required for 1M context", and /context is capped at 200K despite the [1m] variant being selected

Related: #11281 (Sonnet 1M UI shows 1M but API enforces 200K) and #47019 (hasExtraUsageEnabled not synced/overwritten).

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Version 1.12603.1 (3df4fd)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

Org UUID: 12aeeff0-9672-41bc-a94c-5c28e19c338d
Billing: apple_subscription (Pro)
Platform: macOS (Apple Silicon), Claude Desktop app (not CLI/terminal)

Note: the "Server is temporarily limiting requests / Too many requests" banner also appears intermittently, likely related to the ongoing Fable 5 / Mythos 5 incident, but the core issue here is the 1M→200K context cap with usage credits enabled.