Describe the bug

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https://block.github.io/goose/docs/troubleshooting

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A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://github.com/tableau/tableau-mcp
2. Install vanilla version. I used kubernetes and dockerized. Note that I added the CA root to Trust in the keychain. Curl works fine and returns 200
3. Use the tableau-mcp with python web application using https://uri
4. Add Extension (SSE / HTTP), which fails to add extension

Expected behavior
I would expect to be able to load the extension without issues

Screenshots
If applicable, add screenshots to help explain your problem.

Please provide the following information

• OS & Arch:
• Mac OS 26.2
• Interface: [UI / CLI]
• Both CLI and UI
• Version: [e.g. v1.0.2]
• 1.18.0
• Extensions enabled: [e.g. Computer Controller, Figma]
• Developer
• Provider & Model: [e.g. Google – gemini-1.5-pro]
• OpenAI gpt-5-codex

Additional context
Add any other context about the problem here.

diagnostics_20251222_10.zip