src/fastmcp/server/low_level.py

from typing import Any

from mcp.server.lowlevel.server import (
    LifespanResultT,
    NotificationOptions,
    RequestT,
)
from mcp.server.lowlevel.server import (
    Server as _Server,
)
from mcp.server.models import InitializationOptions


class LowLevelServer(_Server[LifespanResultT, RequestT]):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # FastMCP servers support notifications for all components
        self.notification_options = NotificationOptions(
            prompts_changed=True,
            resources_changed=True,
            tools_changed=True,
        )

    def create_initialization_options(
        self,
        notification_options: NotificationOptions | None = None,
        experimental_capabilities: dict[str, dict[str, Any]] | None = None,
        **kwargs: Any,
    ) -> InitializationOptions:
        # ensure we use the FastMCP notification options
        if notification_options is None:
            notification_options = self.notification_options
        return super().create_initialization_options(
            notification_options=notification_options,
            experimental_capabilities=experimental_capabilities,
            **kwargs,
        )