# MCP Server Error

**URL:** <https://community.deeplearning.ai/t/mcp-server-error/894443>\
**Category:** MCP: Build Rich-Context AI Apps with Anthropic\
**Created:** [August 6, 2026, 6:42pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443 "2026-08-06T18:42:02Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![ecocarlisle](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/ecocarlisle/32/160872_2.png) [@ecocarlisle](https://community.deeplearning.ai/u/ecocarlisle)\
**Post date:** [August 6, 2026, 6:42pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/1 "2026-08-06T18:42:02Z")

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![image](https://global.discourse-cdn.com/dlai/original/3X/1/f/1f8f1cb5285ba5672f77bdb0d536527973d1d1a6.png)

I get the following error when I try to connect:  
Traceback (most recent call last): File “/home/jovyan/work/L4/mcp\_project/research\_server.py”, line 6, in from mcp.server.fastmcp import FastMCP ModuleNotFoundError: No module named ‘mcp.server.fastmcp’

Traceback (most recent call last): File “/home/jovyan/work/L4/mcp\_project/research\_server.py”, line 6, in from mcp.server.fastmcp import FastMCP ModuleNotFoundError: No module named ‘mcp.server.fastmcp’

Traceback (most recent call last): File “/home/jovyan/work/L4/mcp\_project/research\_server.py”, line 6, in from mcp.server.fastmcp import FastMCP ModuleNotFoundError: No module named ‘mcp.server.fastmcp’

Traceback (most recent call last): File “/home/jovyan/work/L4/mcp\_project/research\_server.py”, line 6, in from mcp.server.fastmcp import FastMCP ModuleNotFoundError: No module named ‘mcp.server.fastmcp’

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**Author:** ![ecocarlisle](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/ecocarlisle/32/160872_2.png) [@ecocarlisle](https://community.deeplearning.ai/u/ecocarlisle)\
**Post date:** [August 6, 2026, 6:56pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/2 "2026-08-06T18:56:07Z")

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Figured this out. There have been breaking changes to the MCP SDK since this tutorial. You need to do these two things.  
1)update the version of MCP  
2)change the code:  
from mcp.server import MCPServer

PAPER\_DIR = “papers”

# Initialize FastMCP server

mcp = MCPServer(“research”)

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**Author:** ![TMosh](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/tmosh/32/9321_2.png) [@TMosh](https://community.deeplearning.ai/u/TMosh)\
**Post date:** [August 6, 2026, 9:46pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/3 "2026-08-06T21:46:29Z")

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Please concentrate your comments io this course in one thread. It will be easier to track that way.

> [@Still facing the error code: 400 in L3](https://community.deeplearning.ai/t/still-facing-the-error-code-400-in-l3/891748/10):
>
> It seems the whole notebook will be refactored. I’ll ask both teams again.

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**Author:** ![aravindagn](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/aravindagn/32/161357_2.png) [@aravindagn](https://community.deeplearning.ai/u/aravindagn)\
**Post date:** [August 8, 2026, 6:53am UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/6 "2026-08-08T06:53:15Z")

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This is because `uv add mcp` now installs **mcp 2.0.0** , which removed `mcp.server.fastmcp`.

Fix

`cd ~/work/L4/mcp_project`  
`source .venv/bin/activate`  
**`uv add "mcp>=1.2,<2"`**  
`uv run python -c "from mcp.server.fastmcp import FastMCP; print('ok')"`

When that prints `ok`, restart the inspector:

`npx @modelcontextprotocol/inspector uv run research_server.py`

Cheers !

 ![Screenshot 2026-08-08 085253](https://global.discourse-cdn.com/dlai/original/3X/1/a/1a732360c1b78be07f06c71095f114add102e0bf.png)

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**Author:** ![lesly.zerna](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/lesly.zerna/32/47465_2.png) [@lesly.zerna](https://community.deeplearning.ai/u/lesly.zerna)\
**Post date:** [August 13, 2026, 5:16pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/8 "2026-08-13T17:16:47Z")

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Thanks everyone for reporting, suggesting solutions and mostly for your patience! Updates have been pushed to production for all notebooks.

 ![Screenshot 2026-08-13 at 1.15.41 PM](https://global.discourse-cdn.com/dlai/original/3X/d/0/d08e6a402a334d5c1d234ea7abf01c05d838e586.jpeg)

> Note: You may still see some non-blocking warnings in the terminal (npm engine warnings, a `pydantic-settings` warning) — these don’t stop the lessons from working, just noisy output

**Quick status:** the errors you’ve been hitting (`mcp.server.fastmcp` import errors, `McpError` import errors, `tool_use`/`tool_result` mismatches) are due to a breaking update released by MCP on 2026-07-28, which changed parts of the SDK the course was originally built against. This isn’t something on your end — the environment genuinely needs a few extra steps beyond what’s shown in the videos to keep working with today’s package versions.

We’ve pushed markdown notes to L3, L4, L6, and L7 with the exact commands needed to get things running again. Please check those notebooks for the updated instructions.

Happy Learning!

Lesly - DLAI

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**Author:** ![lesly.zerna](https://sea1.discourse-cdn.com/dlai/user_avatar/community.deeplearning.ai/lesly.zerna/32/47465_2.png) [@lesly.zerna](https://community.deeplearning.ai/u/lesly.zerna)\
**Post date:** [August 13, 2026, 5:17pm UTC](https://community.deeplearning.ai/t/mcp-server-error/894443/9 "2026-08-13T17:17:01Z")

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Closed on August 13, 2026, 5:17pm UTC