middleware
FastMCP 4 beta is here — get the latest MCP protocol. See what's new.
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FastMCP 4 beta is here — get the latest MCP protocol. See what's new.
fastmcp.server.middleware.middlewaremark_interior_dispatched mark_interior_dispatched() -> None
make_middleware_wrapper make_middleware_wrapper(middleware: Middleware, call_next: CallNext[T, R]) -> CallNext[T, R]
make_handler_wrapper make_handler_wrapper(handler: Callable[..., Awaitable[Any]], call_next: CallNext[Any, Any]) -> CallNext[Any, Any]
CallNext MiddlewareContext copy copy(self, **kwargs: Any) -> MiddlewareContext[T]
Middleware on_message on_message(self, context: MiddlewareContext[Any], call_next: CallNext[Any, Any]) -> Any
on_request on_request(self, context: MiddlewareContext[mt.Request[Any, Any]], call_next: CallNext[mt.Request[Any, Any], Any]) -> Any
on_notification on_notification(self, context: MiddlewareContext[mt.Notification[Any, Any]], call_next: CallNext[mt.Notification[Any, Any], Any]) -> Any
on_initialize on_initialize(self, context: MiddlewareContext[mt.InitializeRequest], call_next: CallNext[mt.InitializeRequest, mt.InitializeResult | None]) -> mt.InitializeResult | None
on_discover on_discover(self, context: MiddlewareContext[mt.DiscoverRequest], call_next: CallNext[mt.DiscoverRequest, mt.DiscoverResult | dict[str, Any]]) -> mt.DiscoverResult | dict[str, Any]
on_call_tool on_call_tool(self, context: MiddlewareContext[mt.CallToolRequestParams], call_next: CallNext[mt.CallToolRequestParams, ToolResult]) -> ToolResult
on_read_resource on_read_resource(self, context: MiddlewareContext[mt.ReadResourceRequestParams], call_next: CallNext[mt.ReadResourceRequestParams, ResourceResult]) -> ResourceResult
on_get_prompt on_get_prompt(self, context: MiddlewareContext[mt.GetPromptRequestParams], call_next: CallNext[mt.GetPromptRequestParams, PromptResult]) -> PromptResult
on_list_tools on_list_tools(self, context: MiddlewareContext[mt.ListToolsRequest], call_next: CallNext[mt.ListToolsRequest, Sequence[Tool]]) -> Sequence[Tool]
on_list_resources on_list_resources(self, context: MiddlewareContext[mt.ListResourcesRequest], call_next: CallNext[mt.ListResourcesRequest, Sequence[Resource]]) -> Sequence[Resource]
on_list_resource_templates on_list_resource_templates(self, context: MiddlewareContext[mt.ListResourceTemplatesRequest], call_next: CallNext[mt.ListResourceTemplatesRequest, Sequence[ResourceTemplate]]) -> Sequence[ResourceTemplate]
on_list_prompts on_list_prompts(self, context: MiddlewareContext[mt.ListPromptsRequest], call_next: CallNext[mt.ListPromptsRequest, Sequence[Prompt]]) -> Sequence[Prompt]