[BUG] Fable 5 gated behind "Requires usage credits" under CLAUDE_CODE_OAUTH_TOKEN auth — client discards subscriptionType it already has

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

What's Wrong?

When Claude Code authenticates via the CLAUDE_CODE_OAUTH_TOKEN environment variable (e.g. a long-lived token from claude setup-token), the /model picker gates Fable 5 behind "· Requires usage credits" even though:

• the token belongs to a Max 5x account whose plan includes Fable 5,
• the same account on the same machine shows Fable as included when using normal keychain login (claude auth login),
• the API itself happily serves Fable to this exact token: CLAUDE_CODE_OAUTH_TOKEN=... claude --model fable -p "hi" works.

So the gating is purely client-side and contradicts both the account's actual entitlement and the server's behavior.

Root cause (from reading the 2.1.220 bundle): when the token comes from the env var, the credential object is built with the plan metadata hardcoded to null:

if (env.CLAUDE_CODE_OAUTH_TOKEN) return {
  accessToken: ..., refreshToken: null, expiresAt: null,
  scopes: [...],                                            // defaults to ["user:inference"]
  subscriptionType: env.CLAUDE_CODE_SUBSCRIPTION_TYPE || null,
  rateLimitTier: env.CLAUDE_CODE_RATE_LIMIT_TIER || null
};

subscriptionType: null then flows into the plan checks and the feature-flag user context (which omits subscriptionType/rateLimitTier when null), so the model picker treats the session as unknown-plan and falls into the credits-required branch — even though the cached oauthAccount in the config dir's .claude.json says organizationType: "claude_max" from a successful profile fetch. The client has the entitlement data; the picker just doesn't consult it in env-token mode.

Setting the (undocumented) overrides CLAUDE_CODE_SUBSCRIPTION_TYPE=max and CLAUDE_CODE_RATE_LIMIT_TIER=default_claude_max_5x fixes the picker, which confirms the mechanism.

What Should Happen?

With CLAUDE_CODE_OAUTH_TOKEN auth, Claude Code should resolve the plan from the cached oauthAccount profile (or re-fetch it) instead of assuming "no plan", so Fable 5 shows as included for accounts whose plan includes it — matching what the server actually serves and what keychain login shows for the same account.

If env-token sessions are intentionally excluded from subscription model entitlements, the picker message should say that ("not available with long-lived token auth — run /login") rather than the misleading "Requires usage credits", and CLAUDE_CODE_SUBSCRIPTION_TYPE / CLAUDE_CODE_RATE_LIMIT_TIER should be documented.

Error Messages/Logs

# /model picker entry under CLAUDE_CODE_OAUTH_TOKEN auth:
#   Fable  Fable 5 · Most capable for your hardest and longest-running tasks · Requires usage credits
# Same account via keychain login: no "Requires usage credits" suffix, Fable selectable.

Steps to Reproduce

1. On a Max account, mint a long-lived token: claude setup-token.
2. In a fresh shell: export CLAUDE_CODE_OAUTH_TOKEN=<token> (optionally a dedicated CLAUDE_CONFIG_DIR that has completed onboarding with this account).
3. Run claude, open /model → Fable 5 shows "· Requires usage credits" / selection is gated.
4. Exit; run CLAUDE_CODE_OAUTH_TOKEN=<token> claude --model fable -p "reply ok" → succeeds, proving the token is entitled to Fable server-side.
5. Re-run step 3 with CLAUDE_CODE_SUBSCRIPTION_TYPE=max CLAUDE_CODE_RATE_LIMIT_TIER=default_claude_max_5x also exported → Fable shows as included.

Reproduced with two different accounts (Max 5x personal, Team with Fable) on the same machine; both are gated under env-token auth and fine under keychain login (CLI or macOS app).

Claude Model

Other (Fable 5)

Is this a regression?

I don't know

Claude Code Version

2.1.220 (Claude Code)

Platform

Anthropic API (claude.ai subscription auth)

Operating System

macOS

Terminal/Shell

Other (kitty)

Additional Information

Related but distinct: #80749, #79337, #79341, #79576 all report Fable credits-gating under normal keychain login (intermittent / server-side flag causes). This report is deterministic and specific to CLAUDE_CODE_OAUTH_TOKEN auth: the client discards plan metadata it already has. Use case: running two subscriptions side by side via per-account long-lived tokens injected through the env var.