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I noticed that the FastMCP server does not have the options to manually specify the capabilities of the server, however it is possible to do so with the low-level server.
My current workaround to advertise the capabilities is like so:
mcp=FastMCP("test-server")
# Manually set notification optionslowlevel_server: Server=mcp._mcp_serverlowlevel_server.notification_options.resources_changed=Truelowlevel_server.notification_options.tools_changed=True# Now, we override the mcp.run()asyncdefmain():
asyncwithstdio_server() as (r, w):
init_opts=lowlevel_server.create_initialization_options(
lowlevel_server.notification_options,
{}
)
awaitlowlevel_server.run(r, w, init_opts)
if__name__=="__main__":
anyio.run(main)
Is there any other way to specify the capabilities of the FastMCP server? Is there a reason not to?
I noticed that the FastMCP server does not have the options to manually specify the capabilities of the server, however it is possible to do so with the low-level server.
My current workaround to advertise the capabilities is like so:
mcp = FastMCP("test-server")
Manually set notification options
lowlevel_server: Server = mcp._mcp_server
lowlevel_server.notification_options.resources_changed = True
lowlevel_server.notification_options.tools_changed = True
Now, we override the mcp.run()
async def main():
async with stdio_server() as (r, w):
init_opts = lowlevel_server.create_initialization_options(
lowlevel_server.notification_options,
{}
)
await lowlevel_server.run(r, w, init_opts)
if name == "main":
anyio.run(main)
Is there any other way to specify the capabilities of the FastMCP server? Is there a reason not to?
Thanks!
Additional Context
No response
I tried that but chatGPT tried to use the old tool and failed. I also tried a new chat. Was it supposed to request the updated tool list and work without errors?
Activity
felixweinberger commentedon Oct 7, 2025
This is fair and we might want to add some sane defaults versions of these methods - currently FastMCP doesn't have these.
ronytesler commentedon Apr 1, 2026
I tried that but chatGPT tried to use the old tool and failed. I also tried a new chat. Was it supposed to request the updated tool list and work without errors?