Class Server

src/mcp/server/lowlevel/server.py:128–572

class Server(Generic[LifespanResultT]):
    def __init__(
        self,
        name: str,
        *,
        version: str | None = None,
        title: str | None = None,
        description: str | None = None,
        instructions: str | None = None,
        website_url: str | None = None,
        icons: list[types.Icon] | None = None,
        lifespan: Callable[
            [Server[LifespanResultT]],
            AbstractAsyncContextManager[LifespanResultT],
        ] = lifespan,
        # Request handlers
        on_list_tools: Callable[
            [ServerRequestContext[LifespanResultT], types.PaginatedRequestParams | None],
            Awaitable[types.ListToolsResult],
        ]
        | None = None,
        on_call_tool: Callable[
            [ServerRequestContext[LifespanResultT], types.CallToolRequestParams],
            Awaitable[types.CallToolResult | types.InputRequiredResult],
        ]
        | None = None,
        on_list_resources: Callable[
            [ServerRequestContext[LifespanResultT], types.PaginatedRequestParams | None],
            Awaitable[types.ListResourcesResult],
        ]
        | None = None,
        on_list_resource_templates: Callable[
            [ServerRequestContext[LifespanResultT], types.PaginatedRequestParams | None],
            Awaitable[types.ListResourceTemplatesResult],
        ]
        | None = None,
        on_read_resource: Callable[
            [ServerRequestContext[LifespanResultT], types.ReadResourceRequestParams],
            Awaitable[types.ReadResourceResult | types.InputRequiredResult],
        ]
        | None = None,
        on_subscribe_resource: Callable[
            [ServerRequestContext[LifespanResultT], types.SubscribeRequestParams],
            Awaitable[types.EmptyResult],
        ]
        | None = None,
        on_unsubscribe_resource: Callable[
            [ServerRequestContext[LifespanResultT], types.UnsubscribeRequestParams],
            Awaitable[types.EmptyResult],
        ]
        | None = None,
        on_subscriptions_listen: Callable[
            [ServerRequestContext[LifespanResultT], types.SubscriptionsListenRequestParams],
            Awaitable[types.EmptyResult],
        ]
        | None = None,
        on_list_prompts: Callable[
            [ServerRequestContext[LifespanResultT], types.PaginatedRequestParams | None],