[BUG] Can't enable Fast mode

[ilyakamens]

Preflight Checklist

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

What's Wrong?

I suddenly can't enable Fast mode anymore:

❯ /fast on
⎿ Fast mode unavailable: Fast mode has been disabled by your organization

Meanwhile, my organization settings haven't changed. (It happened in the middle of me coding, and I'm the only member of my organization, so no one changed the settings out from under me.)

What Should Happen?

I should be able to enable fast mode.

Error Messages/Logs

Steps to Reproduce

1. Start Claude
2. Try to enable fast mode

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Not sure, perhaps v2.1.50?

Claude Code Version

2.1.59 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

[Ashesh3]

I'm hitting a related issue from a different angle — filed in #29015.

In my case, I use ANTHROPIC_BASE_URL to route traffic through a corporate middleware proxy (required by our network policy). Fast mode is enabled for my org, but Claude Code reports it as disabled.

The root cause is the same mechanism: the penguin mode check (/api/claude_code_penguin_mode) is hardcoded to api.anthropic.com and doesn't respect ANTHROPIC_BASE_URL. When the check fails for any reason — whether it's an org-level misconfiguration (your case), network restrictions (my case), or transient errors — the code defaults to { status: "disabled" } and force-kills fast mode.

The core design issue is that failure = disabled. A more resilient approach would be:

• Fall back to the last known persisted state (penguinModeOrgEnabled in config) instead of force-disabling
• Or keep the status as pending (which already passes availability checks) and retry
• Or at minimum expose an env var override for users who know their org supports it

Your issue and mine are two symptoms of the same brittle check — it assumes the endpoint is always reachable and always returns a correct result, which isn't the case in practice.

[ilyakamens]

Logging out (/logout) and then restarting Claude Code worked. Is it possible my authentication was switched from claude.ai to platform.claude.com during the recent outage? If not, perhaps something related to Fast mode was cached and could only be purged by logging out.

I'm going to close this since I figured it out, even though there definitely is a bug. Given the low activity here and the 6k+ open issues, I don't expect anyone to look at this anytime soon.

[github-actions]

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.