Sandbox does not forward GOOGLE_GENAI_API_VERSION into container #24828

What happened?

When GEMINI_SANDBOX=true is set and GOOGLE_GENAI_API_VERSION is used alongside GOOGLE_GEMINI_BASE_URL to construct a Vertex-compatible API path, the sandbox fails with:

ModelNotFoundError: Not found (404)

sandbox.ts explicitly forwards a hardcoded list of environment variables into the Docker container (e.g., GOOGLE_GEMINI_BASE_URL, GOOGLE_VERTEX_BASE_URL, GOOGLE_GENAI_USE_VERTEXAI). When support for GOOGLE_GENAI_API_VERSION was added in contentGenerator.ts, the corresponding update to sandbox.ts was missed. The variable is available outside the sandbox but silently dropped when entering it.

Without GOOGLE_GENAI_API_VERSION, a GOOGLE_GEMINI_BASE_URL that depends on the API version segment to form a complete URL becomes invalid, and the API returns a 404.

Example

export GOOGLE_GEMINI_BASE_URL="https://my-gateway/vertex/"
export GOOGLE_GENAI_API_VERSION="v1beta1/projects/my-project/locations/global/publishers/google"
export GEMINI_SANDBOX=true
gemini -p "hello"
# => ModelNotFoundError: Not found (404)

Unsetting GEMINI_SANDBOX makes it work.

What did you expect to happen?

GOOGLE_GENAI_API_VERSION should be forwarded into the sandbox container like the other GOOGLE_* environment variables, so that custom Vertex-compatible base URLs work correctly in sandbox mode.

Client information

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│ About Gemini CLI                                                             │
│                                                                              │
│ CLI Version                0.32.1                                            │
│ Git Commit                 4d9d0b3                                           │
│ Model                      Auto (Gemini 3)                                   │
│ Sandbox                    sandbox-0.32.1-0                                  │
│ OS                         linux                                             │
│                                    

Login information

API key

Anything else we need to know?

The environment variable was introduced in #16177 to address #16173, however a small change in sandbox.ts is missing.

Fix:
Add GOOGLE_GENAI_API_VERSION to the forwarded env vars in packages/cli/src/utils/sandbox.ts, in both the Docker path (~line 516) and the LXC envVarsToForward record (~line 957).

I have a fix in my fork but am unable to open a pull request due to the CLA requirement and some build issue. Anyone interested in submitting the PR is welcome to take the change from my commit:
d00e8b5

Workaround

Callers can use the SANDBOX_ENV escape hatch to forward the variable manually (e.g., SANDBOX_ENV=GOOGLE_GENAI_API_VERSION=<value>). This is not ideal because it requires every caller to know about this sandbox implementation detail and shifts the burden of working around an upstream bug to downstream consumers.