diff --git a/design/design.md b/design/design.md
index bfabeac7..33dc3a63 100644
--- a/design/design.md
+++ b/design/design.md
@@ -776,9 +776,9 @@ If a server author wants to support resource subscriptions, they must provide ha
 type ServerOptions struct {
   ...
   // Function called when a client session subscribes to a resource.
-  SubscribeHandler func(context.Context, *SubscribeParams) error
+  SubscribeHandler func(context.Context, ss *ServerSession, *SubscribeParams) error
   // Function called when a client session unsubscribes from a resource.
-  UnsubscribeHandler func(context.Context, *UnsubscribeParams) error
+  UnsubscribeHandler func(context.Context, ss *ServerSession, *UnsubscribeParams) error
 }
 ```
 
diff --git a/mcp/mcp_test.go b/mcp/mcp_test.go
index 819edeb6..da53465c 100644
--- a/mcp/mcp_test.go
+++ b/mcp/mcp_test.go
@@ -78,11 +78,11 @@ func TestEndToEnd(t *testing.T) {
 		ProgressNotificationHandler: func(context.Context, *ServerSession, *ProgressNotificationParams) {
 			notificationChans["progress_server"] <- 0
 		},
-		SubscribeHandler: func(context.Context, *SubscribeParams) error {
+		SubscribeHandler: func(context.Context, *ServerSession, *SubscribeParams) error {
 			notificationChans["subscribe"] <- 0
 			return nil
 		},
-		UnsubscribeHandler: func(context.Context, *UnsubscribeParams) error {
+		UnsubscribeHandler: func(context.Context, *ServerSession, *UnsubscribeParams) error {
 			notificationChans["unsubscribe"] <- 0
 			return nil
 		},
diff --git a/mcp/server.go b/mcp/server.go
index ba2bd0a9..c8878da3 100644
--- a/mcp/server.go
+++ b/mcp/server.go
@@ -66,9 +66,9 @@ type ServerOptions struct {
 	// the session is automatically closed.
 	KeepAlive time.Duration
 	// Function called when a client session subscribes to a resource.
-	SubscribeHandler func(context.Context, *SubscribeParams) error
+	SubscribeHandler func(context.Context, *ServerSession, *SubscribeParams) error
 	// Function called when a client session unsubscribes from a resource.
-	UnsubscribeHandler func(context.Context, *UnsubscribeParams) error
+	UnsubscribeHandler func(context.Context, *ServerSession, *UnsubscribeParams) error
 	// If true, advertises the prompts capability during initialization,
 	// even if no prompts have been registered.
 	HasPrompts bool
@@ -469,7 +469,7 @@ func (s *Server) subscribe(ctx context.Context, ss *ServerSession, params *Subsc
 	if s.opts.SubscribeHandler == nil {
 		return nil, fmt.Errorf("%w: server does not support resource subscriptions", jsonrpc2.ErrMethodNotFound)
 	}
-	if err := s.opts.SubscribeHandler(ctx, params); err != nil {
+	if err := s.opts.SubscribeHandler(ctx, ss, params); err != nil {
 		return nil, err
 	}
 
@@ -488,7 +488,7 @@ func (s *Server) unsubscribe(ctx context.Context, ss *ServerSession, params *Uns
 		return nil, jsonrpc2.ErrMethodNotFound
 	}
 
-	if err := s.opts.UnsubscribeHandler(ctx, params); err != nil {
+	if err := s.opts.UnsubscribeHandler(ctx, ss, params); err != nil {
 		return nil, err
 	}
 
diff --git a/mcp/server_test.go b/mcp/server_test.go
index 0b853a33..5a161b72 100644
--- a/mcp/server_test.go
+++ b/mcp/server_test.go
@@ -281,10 +281,10 @@ func TestServerCapabilities(t *testing.T) {
 				s.AddResourceTemplate(&ResourceTemplate{URITemplate: "file:///rt"}, nil)
 			},
 			serverOpts: ServerOptions{
-				SubscribeHandler: func(ctx context.Context, sp *SubscribeParams) error {
+				SubscribeHandler: func(ctx context.Context, _ *ServerSession, sp *SubscribeParams) error {
 					return nil
 				},
-				UnsubscribeHandler: func(ctx context.Context, up *UnsubscribeParams) error {
+				UnsubscribeHandler: func(ctx context.Context, _ *ServerSession, up *UnsubscribeParams) error {
 					return nil
 				},
 			},
@@ -325,10 +325,10 @@ func TestServerCapabilities(t *testing.T) {
 				s.AddTool(tool, nil)
 			},
 			serverOpts: ServerOptions{
-				SubscribeHandler: func(ctx context.Context, sp *SubscribeParams) error {
+				SubscribeHandler: func(ctx context.Context, _ *ServerSession, sp *SubscribeParams) error {
 					return nil
 				},
-				UnsubscribeHandler: func(ctx context.Context, up *UnsubscribeParams) error {
+				UnsubscribeHandler: func(ctx context.Context, _ *ServerSession, up *UnsubscribeParams) error {
 					return nil
 				},
 				CompletionHandler: func(ctx context.Context, ss *ServerSession, params *CompleteParams) (*CompleteResult, error) {