[BUG] Claude Code uses API billing despite forceLoginMethod: claudeai setting

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?

/feedback Bug: Claude Code uses API billing despite forceLoginMethod: claudeai setting

Environment:

• Claude Code version: 2.0.76
• OS: Arch Linux (6.17.9-arch1-1)

Configuration:

• ~/.claude/settings.json has "forceLoginMethod": "claudeai" set
• ~/.claude/.credentials.json contains valid OAuth tokens with "subscriptionType": "max" and "rateLimitTier": "default_claude_max_20x"
• No ANTHROPIC_API_KEY environment variable is set (verified via env | grep ANTHROPIC)
• No API keys in shell configs (.bashrc, .zshrc, .profile, etc.)

Expected behavior:
Claude Code should use Claude Max subscription (OAuth) for all requests, as configured.

Actual behavior:

• The tmux/terminal UI displays "api" as the account type
• API usage is being billed despite the Max subscription credentials being present and forceLoginMethod being set to claudeai

Steps to reproduce:

1. Set "forceLoginMethod": "claudeai" in ~/.claude/settings.json
2. Login via /login (shows "Login successful")
3. Verify credentials file shows subscriptionType: "max"
4. Start new Claude Code session
5. Observe UI shows "api" instead of expected Max subscription indicator

Impact:
Unexpected API charges when user has an active Claude Max subscription that should be used instead.

What Should Happen?

Expected behavior:
Claude Code should use Claude Max subscription (OAuth) for all requests, as configured. And display max plan and usage.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:

1. Set "forceLoginMethod": "claudeai" in ~/.claude/settings.json
2. Login via /login (shows "Login successful")
3. Verify credentials file shows subscriptionType: "max"
4. Start new Claude Code session
5. Observe UI shows "api" instead of expected Max subscription indicator

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.76

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_