Convert mounted servers to MountedProvider

examples/providers/sqlite/README.md

@@ -12,10 +12,10 @@ This example demonstrates serving MCP tools from a database. Tools can be added,
 
 ```bash
 # Reset the database (optional - tools.db is pre-seeded)
-uv run examples/dynamic_tools_sqlite/setup_db.py
+uv run examples/providers/sqlite/setup_db.py
 
 # Run the server
-uv run fastmcp run examples/dynamic_tools_sqlite/server.py
+uv run fastmcp run examples/providers/sqlite/server.py
 ```
 
 ## How It Works
@@ -50,10 +50,10 @@ While the server is running, you can modify tools in the database:
 
 ```bash
 # Add a new tool
-sqlite3 examples/dynamic_tools_sqlite/tools.db "INSERT INTO tools VALUES ('subtract_numbers', 'Subtract two numbers', '{\"type\":\"object\",\"properties\":{\"a\":{\"type\":\"number\"},\"b\":{\"type\":\"number\"}},\"required\":[\"a\",\"b\"]}', 'subtract', 0, 1)"
+sqlite3 examples/providers/sqlite/tools.db "INSERT INTO tools VALUES ('subtract_numbers', 'Subtract two numbers', '{\"type\":\"object\",\"properties\":{\"a\":{\"type\":\"number\"},\"b\":{\"type\":\"number\"}},\"required\":[\"a\",\"b\"]}', 'subtract', 0, 1)"
 
 # Disable a tool
-sqlite3 examples/dynamic_tools_sqlite/tools.db "UPDATE tools SET enabled = 0 WHERE name = 'divide_numbers'"
+sqlite3 examples/providers/sqlite/tools.db "UPDATE tools SET enabled = 0 WHERE name = 'divide_numbers'"
 ```
 
 The next `list_tools` or `call_tool` request will reflect these changes.

examples/providers/sqlite/server.py

@@ -20,8 +20,9 @@
 import aiosqlite
 from rich import print
 
-from fastmcp import Client, FastMCP, Provider
+from fastmcp import Client, FastMCP
 from fastmcp.server.context import Context
+from fastmcp.server.providers import Provider
 from fastmcp.tools.tool import Tool, ToolResult
 
 DB_PATH = Path(__file__).parent / "tools.db"

examples/providers/sqlite/setup_db.py

@@ -4,7 +4,7 @@
 """
 Creates and seeds the tools database.
 
-Run with: uv run examples/dynamic_tools_sqlite/setup_db.py
+Run with: uv run examples/providers/sqlite/setup_db.py
 """
 
 import asyncio

src/fastmcp/__init__.py

@@ -14,7 +14,6 @@
 
 from fastmcp.server.server import FastMCP
 from fastmcp.server.context import Context
-from fastmcp.providers import Provider
 import fastmcp.server
 
 from fastmcp.client import Client
@@ -32,6 +31,5 @@
     "Client",
     "Context",
     "FastMCP",
-    "Provider",
     "settings",
 ]

src/fastmcp/contrib/component_manager/component_service.py

@@ -7,7 +7,8 @@
 from fastmcp.prompts.prompt import Prompt
 from fastmcp.resources.resource import Resource
 from fastmcp.resources.template import ResourceTemplate
-from fastmcp.server.server import FastMCP, has_resource_prefix, remove_resource_prefix
+from fastmcp.server.providers import MountedProvider
+from fastmcp.server.server import FastMCP
 from fastmcp.tools.tool import Tool
 from fastmcp.utilities.logging import get_logger
 
@@ -40,16 +41,14 @@ async def _enable_tool(self, key: str) -> Tool:
             tool.enable()
             return tool
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if key.startswith(f"{mounted.prefix}_"):
-                    tool_key = key.removeprefix(f"{mounted.prefix}_")
-                    mounted_service = ComponentService(mounted.server)
-                    tool = await mounted_service._enable_tool(tool_key)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_tool_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
+                    tool = await mounted_service._enable_tool(unprefixed)
                     return tool
-                else:
-                    continue
         raise NotFoundError(f"Unknown tool: {key}")
 
     async def _disable_tool(self, key: str) -> Tool:
@@ -69,16 +68,14 @@ async def _disable_tool(self, key: str) -> Tool:
             tool.disable()
             return tool
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if key.startswith(f"{mounted.prefix}_"):
-                    tool_key = key.removeprefix(f"{mounted.prefix}_")
-                    mounted_service = ComponentService(mounted.server)
-                    tool = await mounted_service._disable_tool(tool_key)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_tool_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
+                    tool = await mounted_service._disable_tool(unprefixed)
                     return tool
-                else:
-                    continue
         raise NotFoundError(f"Unknown tool: {key}")
 
     async def _enable_resource(self, key: str) -> Resource | ResourceTemplate:
@@ -102,18 +99,16 @@ async def _enable_resource(self, key: str) -> Resource | ResourceTemplate:
             template.enable()
             return template
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if has_resource_prefix(key, mounted.prefix):
-                    key = remove_resource_prefix(key, mounted.prefix)
-                    mounted_service = ComponentService(mounted.server)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_resource_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
                     mounted_resource: (
                         Resource | ResourceTemplate
-                    ) = await mounted_service._enable_resource(key)
+                    ) = await mounted_service._enable_resource(unprefixed)
                     return mounted_resource
-            else:
-                continue
         raise NotFoundError(f"Unknown resource: {key}")
 
     async def _disable_resource(self, key: str) -> Resource | ResourceTemplate:
@@ -137,18 +132,16 @@ async def _disable_resource(self, key: str) -> Resource | ResourceTemplate:
             template.disable()
             return template
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if has_resource_prefix(key, mounted.prefix):
-                    key = remove_resource_prefix(key, mounted.prefix)
-                    mounted_service = ComponentService(mounted.server)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_resource_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
                     mounted_resource: (
                         Resource | ResourceTemplate
-                    ) = await mounted_service._disable_resource(key)
+                    ) = await mounted_service._disable_resource(unprefixed)
                     return mounted_resource
-            else:
-                continue
         raise NotFoundError(f"Unknown resource: {key}")
 
     async def _enable_prompt(self, key: str) -> Prompt:
@@ -168,16 +161,14 @@ async def _enable_prompt(self, key: str) -> Prompt:
             prompt.enable()
             return prompt
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if key.startswith(f"{mounted.prefix}_"):
-                    prompt_key = key.removeprefix(f"{mounted.prefix}_")
-                    mounted_service = ComponentService(mounted.server)
-                    prompt = await mounted_service._enable_prompt(prompt_key)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_tool_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
+                    prompt = await mounted_service._enable_prompt(unprefixed)
                     return prompt
-                else:
-                    continue
         raise NotFoundError(f"Unknown prompt: {key}")
 
     async def _disable_prompt(self, key: str) -> Prompt:
@@ -196,14 +187,12 @@ async def _disable_prompt(self, key: str) -> Prompt:
             prompt.disable()
             return prompt
 
-        # 2. Check mounted servers using the filtered protocol path.
-        for mounted in reversed(self._server._mounted_servers):
-            if mounted.prefix:
-                if key.startswith(f"{mounted.prefix}_"):
-                    prompt_key = key.removeprefix(f"{mounted.prefix}_")
-                    mounted_service = ComponentService(mounted.server)
-                    prompt = await mounted_service._disable_prompt(prompt_key)
+        # 2. Check mounted servers via MountedProvider
+        for provider in self._server._providers:
+            if isinstance(provider, MountedProvider):
+                unprefixed = provider._strip_tool_prefix(key)
+                if unprefixed is not None:
+                    mounted_service = ComponentService(provider.server)
+                    prompt = await mounted_service._disable_prompt(unprefixed)
                     return prompt
-                else:
-                    continue
         raise NotFoundError(f"Unknown prompt: {key}")

src/fastmcp/server/providers/__init__.py

@@ -0,0 +1,36 @@
+"""Providers for dynamic MCP components.
+
+This module provides the `Provider` abstraction for providing tools,
+resources, and prompts dynamically at runtime.
+
+Example:
+    ```python
+    from fastmcp import FastMCP
+    from fastmcp.server.providers import Provider
+    from fastmcp.tools import Tool
+
+    class DatabaseProvider(Provider):
+        def __init__(self, db_url: str):
+            self.db = Database(db_url)
+
+        async def list_tools(self) -> list[Tool]:
+            rows = await self.db.fetch("SELECT * FROM tools")
+            return [self._make_tool(row) for row in rows]
+
+        async def get_tool(self, name: str) -> Tool | None:
+            row = await self.db.fetchone("SELECT * FROM tools WHERE name = ?", name)
+            return self._make_tool(row) if row else None
+
+    mcp = FastMCP("Server", providers=[DatabaseProvider(db_url)])
+    ```
+"""
+
+from fastmcp.server.providers.base import Components, Provider, TaskComponents
+from fastmcp.server.providers.mounted import MountedProvider
+
+__all__ = [
+    "Components",
+    "MountedProvider",
+    "Provider",
+    "TaskComponents",
+]