Struct ProxyServer 

pub struct ProxyServer { /* private fields */ }

MCP server handler that proxies requests to an upstream MCP server.

ProxyServer intercepts every call_tool response and applies the FilterEngine pipeline before returning results to Claude, while list_tools responses are forwarded as-is.

The filter engine is held behind an ArcSwap so it can be atomically replaced at runtime when external presets change on disk (hot reload).

Examples

let config = Arc::new(Config::from_upstream(&["npx", "some-mcp"], None).unwrap());
let engine = Arc::new(ArcSwap::from(Arc::new(FilterEngine::new(config))));
// let proxy = ProxyServer::new(engine, None, upstream_peer);

Implementations

impl ProxyServer

pub fn new( engine: Arc<ArcSwap<FilterEngine>>, tracker: Option<Arc<Tracker>>, upstream: Peer<RoleClient>, ) -> Self

Create a new proxy server with an already-connected upstream peer.

Arguments

• engine — The shared, hot-reloadable filter engine.
• tracker — Optional Tracker for recording token savings.
• upstream — Peer handle to the upstream MCP server.

Trait Implementations

impl Clone for ProxyServer

fn clone(&self) -> ProxyServer

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl ServerHandler for ProxyServer

fn get_info(&self) -> ServerInfo

fn get_peer(&self) -> Option<Peer<RoleServer>>

fn set_peer(&mut self, peer: Peer<RoleServer>)

fn list_tools( &self, request: PaginatedRequestParam, _context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<ListToolsResult, McpError>> + Send + '_

fn call_tool( &self, request: CallToolRequestParam, _context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<CallToolResult, McpError>> + Send + '_

fn ping( &self, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<(), ErrorData>> + Send

fn initialize( &self, request: InitializeRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<InitializeResult, ErrorData>> + Send

fn complete( &self, request: CompleteRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<CompleteResult, ErrorData>> + Send

fn set_level( &self, request: SetLevelRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<(), ErrorData>> + Send

fn get_prompt( &self, request: GetPromptRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<GetPromptResult, ErrorData>> + Send

fn list_prompts( &self, request: Option<PaginatedRequestParamInner>, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<ListPromptsResult, ErrorData>> + Send

fn list_resources( &self, request: Option<PaginatedRequestParamInner>, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<ListResourcesResult, ErrorData>> + Send

fn list_resource_templates( &self, request: Option<PaginatedRequestParamInner>, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<ListResourceTemplatesResult, ErrorData>> + Send

fn read_resource( &self, request: ReadResourceRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<ReadResourceResult, ErrorData>> + Send

fn subscribe( &self, request: SubscribeRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<(), ErrorData>> + Send

fn unsubscribe( &self, request: UnsubscribeRequestParam, context: RequestContext<RoleServer>, ) -> impl Future<Output = Result<(), ErrorData>> + Send

fn on_cancelled( &self, notification: CancelledNotificationParam, ) -> impl Future<Output = ()> + Send

fn on_progress( &self, notification: ProgressNotificationParam, ) -> impl Future<Output = ()> + Send

fn on_initialized(&self) -> impl Future<Output = ()> + Send

fn on_roots_list_changed(&self) -> impl Future<Output = ()> + Send