fix(mcp): Ensure that stdio MCP server execution has the GEMINI_CLI=1 env variable populated.

[richieforeman]

Summary

Centralizes the definition and value of the GEMINI_CLI=1 env variable. Uses it within MCP stdio execution

Details

This variable is used by sub processes to detect that they're being used from GCLI.

Related Issues

N/A

How to Validate

When an STDIO MCP server is executed, the GEMINI_CLI=1 env variable should be present.

Pre-Merge Checklist

• [n/a] Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• [n/a] Noted breaking changes (if any)
• Validated on required platforms/methods:
  • MacOS
    • npm run
    • npx
    • Docker
    • Podman
    • Seatbelt
  • Windows
    • npm run
    • npx
    • Docker
  • Linux
    • npm run
    • npx
    • Docker

[gemini-code-assist]

Summary of Changes

Hello @richieforeman, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request standardizes the mechanism by which sub-processes can identify that they are being executed from within the Gemini CLI. It achieves this by centralizing the definition of the GEMINI_CLI environment variable and ensuring its consistent application to all relevant shell and MCP server executions, improving reliability and maintainability.

Highlights

• Centralized Environment Variable Definition: The GEMINI_CLI environment variable, used for identifying executions originating from the Gemini CLI, has been centralized into new constants (GEMINI_CLI_IDENTIFICATION_ENV_VAR and GEMINI_CLI_IDENTIFICATION_ENV_VAR_VALUE) for consistent usage.
• Consistent Application for MCP Servers: Ensured that the GEMINI_CLI=1 environment variable is consistently applied to stdio MCP server executions, allowing sub-processes to reliably detect their execution context.
• Added Test Coverage: A new test case was added to validate that the GEMINI_CLI environment variable is correctly set in the environment when creating MCP client transports.

Changelog

• packages/core/src/services/shellExecutionService.ts
  • Introduced GEMINI_CLI_IDENTIFICATION_ENV_VAR and GEMINI_CLI_IDENTIFICATION_ENV_VAR_VALUE constants.
  • Updated the ShellExecutionService to use these new constants when setting the GEMINI_CLI environment variable for child processes.
• packages/core/src/tools/mcp-client.test.ts
  • Added a new test it('sets the GEMINI_CLI env var for the execution') to verify the presence of GEMINI_CLI: '1' in the environment passed to StdioClientTransport.
• packages/core/src/tools/mcp-client.ts
  • Imported the GEMINI_CLI_IDENTIFICATION_ENV_VAR and GEMINI_CLI_IDENTIFICATION_ENV_VAR_VALUE constants.
  • Modified the createTransport function to explicitly include GEMINI_CLI_IDENTIFICATION_ENV_VAR with its defined value in the environment for MCP server processes.

Activity

• No human activity (comments, reviews, etc.) has been recorded on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request improves maintainability by centralizing the GEMINI_CLI environment variable and correctly applying new constants for stdio MCP server and child process executions. While no vulnerabilities were found, this was due to an issue with the provided file contents, which prevented a thorough security analysis. For code improvements, it's suggested to use relative paths for imports in mcp-client.ts, utilize the new constants in mcp-client.test.ts for tests, and consider refactoring the hardcoded GEMINI_CLI variable in the executeWithPty method within shellExecutionService.ts for a more complete solution.

[github-actions]

Size Change: +450 B (0%)

Total Size: 24.3 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	24.3 MB	+450 B (0%)
./bundle/sandbox-macos-permissive-closed.sb	1.03 kB	0 B
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-closed.sb	3.29 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B

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