[BUG] Claude Code fails to login via the Anthropic Console in VSCode when using devcontainers

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?

I am trying to use the Claude Code extension in VSCode with a devcontainer. When I try and login via /login, it prompts me to select a login method. When I select Anthropic Console, I authenticate, however when I try and use the Claude Code extension window it fails with Invalid API key · Please run /login. This happens in a loop. Note, this doesn't happen for me when not using a devcontainer.json setup.

What Should Happen?

I should be able to login to Claude Code with /login from within the container setup by the devcontainer.json file.

Error Messages/Logs

Here is what I see in the VSCode output window:


2025-12-18 21:31:10.956 [info] From claude: 2025-12-18T21:31:10.956Z [DEBUG] Getting matching hook commands for UserPromptSubmit with query: undefined
2025-12-18T21:31:10.956Z [DEBUG] Found 0 hook matchers in settings
2025-12-18T21:31:10.956Z [DEBUG] Matched 0 unique hooks for query "no match query" (0 before deduplication)

2025-12-18 21:31:10.967 [info] From claude: 2025-12-18T21:31:10.966Z [DEBUG] FileHistory: Making snapshot for message 6e3e397b-d1e9-4974-a80c-89081f7cf5a0

2025-12-18 21:31:10.967 [info] From claude: 2025-12-18T21:31:10.967Z [DEBUG] FileHistory: Added snapshot for 6e3e397b-d1e9-4974-a80c-89081f7cf5a0, tracking 0 files

2025-12-18 21:31:10.986 [info] From claude: 2025-12-18T21:31:10.986Z [ERROR] Error streaming, falling back to non-streaming mode: Could not resolve authentication method. Expected either apiKey or authToken to be set. Or for one of the "X-Api-Key" or "Authorization" headers to be explicitly omitted

2025-12-18 21:31:10.994 [info] From claude: 2025-12-18T21:31:10.989Z [ERROR] Error in non-streaming fallback: Could not resolve authentication method. Expected either apiKey or authToken to be set. Or for one of the "X-Api-Key" or "Authorization" headers to be explicitly omitted
2025-12-18T21:31:10.989Z [ERROR] "Error: Error: Could not resolve authentication method. Expected either apiKey or authToken to be set. Or for one of the \"X-Api-Key\" or \"Authorization\" headers to be explicitly omitted\n    at validateHeaders (/$bunfs/root/claude:811:1013)\n    at buildHeaders (/$bunfs/root/claude:811:8516)\n    at async buildRequest (/$bunfs/root/claude:811:7582)\n    at async makeRequest (/$bunfs/root/claude:811:3410)\n    at processTicksAndRejections (native:7:39)"

Steps to Reproduce

1. Setup a new project with a .devcontainer/devcontainer.json file e.g.:

{
  "name": "Python Dev Container",
  "build": {
    "dockerfile": "../Dockerfile"
  },
  "customizations": {
    "vscode": {
      "extensions": [
        "ms-python.python",
        "ms-python.vscode-pylance",
        "anthropic.claude-code"
      ],
      "settings": {
        "python.defaultInterpreterPath": "/usr/local/bin/python",
        "python.linting.enabled": true,
        "python.formatting.provider": "black"
      }
    }
  },
  "forwardPorts": [8000],
  "postCreateCommand": "pip install -r requirements.txt",
  "remoteUser": "root"
}

1. Open Claude Code extension
2. Try and login via /login

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.0.72 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

_No response_