Unhandled Promise Rejection: "TypeError: fetch failed" in Gemini CLI (Undici / StreamableHTTPClientTransport)

[lifevideogame]

What happened?

Running the Gemini CLI triggers an unhandled Promise rejection. The CLI itself prints:

“This is an unexpected error. Please file a bug report using the /bug tool.”

The error appears to originate from the HTTP transport layer used by @google/gemini-cli and @modelcontextprotocol/sdk. Here is the exact output:

This is an unexpected error. Please file a bug report using the /bug tool.
CRITICAL: Unhandled Promise Rejection!

Reason: TypeError: fetch failed
Stack trace:
TypeError: fetch failed
at /home/lucia/.nvm/versions/node/v20.19.4/lib/node_modules/@google/gemini-cli/node_modules/undici/index.js:124:13
at async file:///home/lucia/.nvm/versions/node/v20.19.4/lib/node_modules/@google/gemini-cli/node_modules/@google/gemini-cli-core/dist/src/ide/ide-client.js:512:30
at async StreamableHTTPClientTransport.send (file:///home/lucia/.nvm/versions/node/v20.19.4/lib/node_modules/@google/gemini-cli/node_modules/@modelcontextprotocol/sdk/dist/esm/client/streamableHttp.js:278:30) (x2)

What did you expect to happen?

The Gemini CLI should gracefully handle network/transport failures instead of throwing an unhandled Promise rejection. Ideally, the error should be caught and surfaced with a stable error message rather than a crash coming from Undici and StreamableHTTPClientTransport.

Client information

• CLI Version: 0.17.1
• Git Commit: 1d51935
• Session ID: fd3a5c20-f260-473c-9993-ec1d49049b1a
• Operating System: linux v20.19.4
• Sandbox Environment: no sandbox
• Model Version: auto
• Memory Usage: 337.2 MB
• IDE Client: VS Code

Login information

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Anything else we need to know?

No response

[gemini-cli]

Found possible duplicate issues:

• CRITICAL: Unhandled Promise Rejection! #10441
• CRITICAL: Unhandled Promise Rejection! #10707
• Unhandled Promise Rejection: TypeError - fetch failed in Gemini CLI #10059
• Unhandled Promise Rejection! #12205
• Crash #10457
• Gemini CLI crashed and stopped responding #10389
• CRITICAL: Unhandled Promise Rejection! #10214
• Gemini crash #10062
• Today,The error has always occcured when I use gemini-cli in vscode #9878
• CRITICAL: Unhandled Promise Rejection! #10833

If you believe this is not a duplicate, please remove the status/possible-duplicate label.

[galz10]

Hi @lifevideogame , seems like there are a couple duplicate issues will consolidate to a single one, so closing this out please follow updates in #14102.