URL: https://gofastmcp.com/servers/providers/local
Title: Local Provider - FastMCP

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On this page
How It Works
Component Registration
Using Decorators
Using Direct Methods
Removing Components
Duplicate Handling
Component Visibility
Standalone LocalProvider
MCP Providers
Local Provider
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The default provider for decorator-registered components
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New in version
3.0.0
LocalProvider
stores components that you define directly on your server. When you use
@mcp.tool
,
@mcp.resource
, or
@mcp.prompt
, you’re adding components to your server’s
LocalProvider
.
​
How It Works
Every FastMCP server has a
LocalProvider
as its first provider. Components registered via decorators or direct methods are stored here:
from
fastmcp
import
FastMCP
mcp
=
FastMCP
(
"
MyServer
"
)
# These are stored in the server's `LocalProvider`
@
mcp
.
tool
def
greet
(
name
:
str
)
->
str
:
"""
Greet someone by name.
"""
return
f
"Hello,
{
name
}
!"
@
mcp
.
resource
(
"
data://config
"
)
def
get_config
()
->
str
:
"""
Return configuration data.
"""
return
'
{"version": "1.0"}
'
@
mcp
.
prompt
def
analyze
(
topic
:
str
)
->
str
:
"""
Create an analysis prompt.
"""
return
f
"Please analyze:
{
topic
}
"
The
LocalProvider
is always queried first when clients request components, ensuring that your directly-defined components take precedence over those from mounted or proxied servers.
​
Component Registration
​
Using Decorators
The most common way to register components:
@
mcp
.
tool
def
my_tool
(
x
:
int
)
->
str
:
return
str
(
x
)
@
mcp
.
resource
(
"
data://info
"
)
def
my_resource
()
->
str
:
return
"
info
"
@
mcp
.
prompt
def
my_prompt
(
topic
:
str
)
->
str
:
return
f
"Discuss:
{
topic
}
"
​
Using Direct Methods
You can also add pre-built component objects:
from
fastmcp
.
tools
import
Tool
# Create a tool object
my_tool
=
Tool
.
from_function
(
some_function
,
name
=
"
custom_tool
"
)
# Add it to the server
mcp
.
add_tool
(
my_tool
)
mcp
.
add_resource
(
my_resource
)
mcp
.
add_prompt
(
my_prompt
)
​
Removing Components
Remove components by name or URI:
mcp
.
local_provider
.
remove_tool
(
"
my_tool
"
)
mcp
.
local_provider
.
remove_resource
(
"
data://info
"
)
mcp
.
local_provider
.
remove_prompt
(
"
my_prompt
"
)
​
Duplicate Handling
When you try to add a component that already exists, the behavior depends on the
on_duplicate
setting:
Mode
Behavior
"error"
(default)
Raise
ValueError
"warn"
Log warning and replace
"replace"
Silently replace
"ignore"
Keep existing component
Configure this when creating the server:
mcp
=
FastMCP
(
"
MyServer
"
,
on_duplicate
=
"
warn
"
)
​
Component Visibility
New in version
3.0.0
Components can be dynamically enabled or disabled at runtime. Disabled components don’t appear in listings and can’t be called.
@
mcp
.
tool
(
tags
={
"
admin
"
})
def
delete_all
()
->
str
:
"""
Delete everything.
"""
return
"
Deleted
"
@
mcp
.
tool
def
get_status
()
->
str
:
"""
Get system status.
"""
return
"
OK
"
# Disable admin tools
mcp
.
disable
(
tags
={
"
admin
"
})
# Or only enable specific tools
mcp
.
enable
(
keys
={
"
tool:get_status
"
},
only
=
True
)
See
Visibility
for the full documentation on keys, tags, allowlist mode, and provider-level control.
​
Standalone LocalProvider
You can create a LocalProvider independently and attach it to multiple servers:
from
fastmcp
import
FastMCP
from
fastmcp
.
server
.
providers
import
LocalProvider
# Create a reusable provider
shared_tools
=
LocalProvider
()
@
shared_tools
.
tool
def
greet
(
name
:
str
)
->
str
:
return
f
"Hello,
{
name
}
!"
@
shared_tools
.
resource
(
"
data://version
"
)
def
get_version
()
->
str
:
return
"
1.0.0
"
# Attach to multiple servers
server1
=
FastMCP
(
"
Server1
"
,
providers
=[
shared_tools
])
server2
=
FastMCP
(
"
Server2
"
,
providers
=[
shared_tools
])
This is useful for:
Sharing components across servers
Testing components in isolation
Building reusable component libraries
Standalone providers also support visibility control with
enable()
and
disable()
. See
Visibility
for details.
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