@mcp.resource with dynamic parameters example don't work

[CNSeniorious000]

In the README, there is an example:

@mcp.resource("users://{user_id}/profile")
def get_user_profile(user_id: str) -> str:
    """Dynamic user data"""
    return f"Profile data for user {user_id}"

This don't work

I can't see any resources in the mcp inspector

[vemonet]

Same for me, I copied the example server from README.md

from fastmcp import FastMCP

# Create an MCP server
mcp = FastMCP("Demo")


# Add an addition tool
@mcp.tool()
def add(a: int, b: int) -> int:
    """Add two numbers"""
    return a + b


# Add a dynamic greeting resource
@mcp.resource("greeting://{name}")
def get_greeting(name: str) -> str:
    """Get a personalized greeting"""
    return f"Hello, {name}!"


if __name__ == "__main__":
    mcp.run()

Then started the inspector with:

uv run fastmcp dev fastmcp.py

I can see the add tool but I get errors for the resource in Error output from MCP server

[12/10/24 17:30:03] INFO Processing request of type __init__.py:431 ListResourcesRequest 

(btw it's a bit weird that the log is labelled as INFO in the error output, not sure if this is a bug or a feature :) )

In history I have:

resources/list▼
Request:

{
  "method": "resources/list",
  "params": {}
}

Response:

{
  "resources": []
}

@jlowin

[mcp2everything]

Anyone got a solution to this problem? Thanks.

[gmr]

It appears to be an issue when there is a parameter for a resource. Resources without parameters appear to work fine.

[micpst]

This is related to #10, the current version of fastmcp simply doesn't support resource templates listing

[zzstoatzz]

hi all @micpst @gmr @mcp2everything @vemonet @CNSeniorious000 - ICYMI

https://github.com/jlowin/fastmcp?tab=readme-ov-file#-fastmcp-has-been-added-to-the-official-mcp-sdk-

[micpst]

@zzstoatzz thanks my bad, seems to be fixed but not released yet

[ICeZer0]

I'm having a similar issue on the official python-sdk. I can't get any resource params to show up in my MCP Inspector, might have to switch to native.

This works fine.

@mcp.resource("config://app")
def get_config() -> str:
    """Static configuration data"""
    return "App configuration here"

Once I add an input param it does not show up as a listed resource

@mcp.resource("users://{hello}/message")
def get_config(hello: str) -> str:
    """dynamic user message"""
    return "Message here {hello}"