Add experimental tags

Author: Quinn-With-Two-Ns

nexus/operation.go

@@ -16,6 +16,8 @@ import (
 type NoValue *struct{}
 
 // OperationOptions contains the general options for an operation, across different handlers.
+//
+// NOTE: Experimental
 type OperationOptions struct {
 	// ServiceName is the name of the service that contains the operation.
 	ServiceName string
@@ -32,6 +34,10 @@ type OperationOptions struct {
 	Header Header
 }
 
+// MiddlewareFunc is a function which receives an OperationInvoker and returns another OperationInvoker.
+// If the middleware wants to stop the chain before any handler is called, it can return an error.
+//
+// NOTE: Experimental
 type MiddlewareFunc func(OperationOptions, OperationInvoker[any, any]) (OperationInvoker[any, any], error)
 
 // OperationReference provides a typed interface for invoking operations. Every [Operation] is also an
@@ -241,6 +247,8 @@ func (r *ServiceRegistry) Register(services ...*Service) error {
 }
 
 // Use registers middleware to be applied to all operations. Middleware is called for each operation invocation.
+//
+// NOTE: Experimental
 func (s *ServiceRegistry) Use(middleWare ...MiddlewareFunc) {
 	s.middleware = append(s.middleware, middleWare...)
 }