[BUG] Claude keeps asking to log in, when using GCP Vertex AI model

[marcopellegrino-devoteam]

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?

When opening Claude, it keeps welcoming me to:

1. set up theme
2. login:

Claude Code can be used with your Claude subscription or billed based on API usage through your Console account.

Select login method:

❯ 1. Claude account with subscription · Pro, Max, Team, or Enterprise

2. Anthropic Console account · API usage billing

I have already setup and loaded an .env var file:

CLAUDE_CODE_USE_VERTEX=1
PROJECT_ID=my-project
CLOUD_ML_REGION=global
ANTHROPIC_VERTEX_PROJECT_ID=my-project
ANTHROPIC_VERTEXAI_REGION=europe-west1

and authenticated in GCP:

gcloud auth login
gcloud auth application-default login

it used to work till 2 days ago, then I upgrade to 2.0.64 and now 2.0.65 and this error shows up.
The problem happens both on MacOs terminal and VSCode terminal.

What Should Happen?

When running claude I should be able to bypass the login using the .env credentials.

Error Messages/Logs

> Claude Code can be used with your Claude subscription or billed based on API usage through your Console account.
> 
>  Select login method:
> 
>  ❯ 1. Claude account with subscription · Pro, Max, Team, or Enterprise
> 
>    2. Anthropic Console account · API usage billing

Steps to Reproduce

Run claude

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

No response

Claude Code Version

2.0.65

Platform

Google Vertex AI

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

No response

[github-actions]

Found 3 possible duplicate issues:

1. [BUG] [Claude Code VS Code Extension]Keep asking for login even if I am using third party provider [vertex] #9136
2. [BUG] VS Code extension ignores third-party provider environment variables during authentication check #12361
3. [BUG] Authentication with "GOOGLE_APPLICATION_CREDENTIALS" does not seem to work #11130

This issue will be automatically closed as a duplicate in 3 days.

• If your issue is a duplicate, please close it and 👍 the existing issue instead
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🤖 Generated with Claude Code

[marcopellegrino-devoteam]

Fyi it works with 2.0.56

[github-actions]

This issue has been inactive for 30 days. If the issue is still occurring, please comment to let us know. Otherwise, this issue will be automatically closed in 30 days for housekeeping purposes.

[github-actions]

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

[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.