diff --git a/room-service/handler.go b/room-service/handler.go
index bf83b2683..7cf44b24d 100644
--- a/room-service/handler.go
+++ b/room-service/handler.go
@@ -369,7 +369,7 @@ func (h *Handler) listMembers(c *natsrouter.Context) (*model.ListRoomMembersResp
 	requesterAccount := c.Param("account")
 	roomID := c.Param("roomID")
 
-	_, err := h.store.GetSubscription(ctx, requesterAccount, roomID)
+	err := h.store.CheckMembership(ctx, requesterAccount, roomID)
 	switch {
 	case errors.Is(err, model.ErrSubscriptionNotFound):
 		return nil, errNotRoomMember
@@ -405,7 +405,7 @@ func (h *Handler) getRoomKey(c *natsrouter.Context) (*model.RoomKeyGetResponse,
 	requesterAccount := c.Param("account")
 	roomID := c.Param("roomID")
 
-	_, err := h.store.GetSubscription(ctx, requesterAccount, roomID)
+	err := h.store.CheckMembership(ctx, requesterAccount, roomID)
 	switch {
 	case errors.Is(err, model.ErrSubscriptionNotFound):
 		return nil, errNotRoomMember
@@ -475,7 +475,7 @@ func (h *Handler) requireMembershipAndGetRoom(ctx context.Context, account, room
 	wg.Add(2)
 	go func() {
 		defer wg.Done()
-		_, subErr = h.store.GetSubscription(ctx, account, roomID)
+		subErr = h.store.CheckMembership(ctx, account, roomID)
 	}()
 	go func() {
 		defer wg.Done()
@@ -983,7 +983,7 @@ func (h *Handler) expandChannelRefs(ctx context.Context, requester string, refs
 		refCtx, cancel := h.contextWithMemberListTimeout(ctx)
 
 		if ref.SiteID == h.siteID {
-			if _, subErr := h.store.GetSubscription(refCtx, requester, ref.RoomID); subErr != nil {
+			if subErr := h.store.CheckMembership(refCtx, requester, ref.RoomID); subErr != nil {
 				cancel()
 				if errors.Is(subErr, context.DeadlineExceeded) {
 					return nil, nil, errcode.Unavailable(fmt.Sprintf("timeout listing members of channel %s@%s", ref.RoomID, ref.SiteID))
@@ -1399,8 +1399,7 @@ func (h *Handler) messageReadReceipt(c *natsrouter.Context, req model.ReadReceip
 	)
 	g, gctx := errgroup.WithContext(ctx)
 	g.Go(func() error {
-		_, err := h.store.GetSubscription(gctx, requesterAccount, roomID)
-		subErr = err
+		subErr = h.store.CheckMembership(gctx, requesterAccount, roomID)
 		return nil
 	})
 	g.Go(func() error {
@@ -1467,7 +1466,7 @@ func (h *Handler) messageThreadRead(c *natsrouter.Context, req model.MessageThre
 	)
 	var g errgroup.Group
 	g.Go(func() error {
-		_, err := h.store.GetSubscription(ctx, account, roomID)
+		err := h.store.CheckMembership(ctx, account, roomID)
 		subErr = err
 		return err
 	})
@@ -1742,11 +1741,11 @@ func (h *Handler) roomRestricted(c *natsrouter.Context, req model.RoomRestricted
 	isTransition := req.Restricted && !room.Restricted
 
 	if req.Restricted && req.OwnerAccount != "" {
-		if _, subErr := h.store.GetSubscription(ctx, req.OwnerAccount, req.RoomID); subErr != nil {
-			if errors.Is(subErr, mongo.ErrNoDocuments) || errors.Is(subErr, model.ErrSubscriptionNotFound) {
+		if subErr := h.store.CheckMembership(ctx, req.OwnerAccount, req.RoomID); subErr != nil {
+			if errors.Is(subErr, model.ErrSubscriptionNotFound) {
 				return nil, errOwnerNotMember
 			}
-			return nil, fmt.Errorf("get owner subscription: %w", subErr)
+			return nil, fmt.Errorf("check owner membership: %w", subErr)
 		}
 	}
 	if isTransition {
diff --git a/room-service/handler_teams_test.go b/room-service/handler_teams_test.go
index 1b6169047..183e9fa17 100644
--- a/room-service/handler_teams_test.go
+++ b/room-service/handler_teams_test.go
@@ -167,8 +167,8 @@ func TestTeamsRoomCall_Success_ExcludesSelf(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").
 		Return(&model.Room{ID: "r1", Name: "general", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
@@ -200,8 +200,8 @@ func TestTeamsRoomCall_RoomIDMissing(t *testing.T) {
 func TestTeamsRoomCall_NotMember(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(nil, model.ErrSubscriptionNotFound)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(model.ErrSubscriptionNotFound)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").
 		Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 
@@ -213,7 +213,7 @@ func TestTeamsRoomCall_NotMember(t *testing.T) {
 func TestTeamsRoomCall_NoOtherMembers(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice")}, nil)
@@ -227,7 +227,7 @@ func TestTeamsRoomCall_NoOtherMembers(t *testing.T) {
 func TestTeamsRoomCall_TooManyMembers(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 
 	members := []model.RoomMember{indMember("alice")}
@@ -271,7 +271,7 @@ func TestTeamsMeeting_CreatesAndPublishes(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Name: "general", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice"), indMember("bob")}, nil)
@@ -335,7 +335,7 @@ func TestTeamsMeeting_Idempotent_FastPathReadHit(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 	// ListRoomMembers must NOT be called when a record already exists.
 
@@ -374,7 +374,7 @@ func TestTeamsMeeting_DuplicateKey_ReturnsExisting(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice")}, nil)
@@ -429,7 +429,7 @@ func TestTeamsMeeting_Concurrent_SingleCreateSingleMessage(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 	// Both goroutines run the membership/room/member reads; allow any count.
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil).AnyTimes()
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil).AnyTimes()
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil).AnyTimes()
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice")}, nil).AnyTimes()
@@ -507,7 +507,7 @@ func TestTeamsMeeting_RoomIDMissing(t *testing.T) {
 func TestTeamsMeeting_NotMember(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(nil, model.ErrSubscriptionNotFound)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(model.ErrSubscriptionNotFound)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 
 	graph := &fakeGraphClient{}
@@ -521,7 +521,7 @@ func TestTeamsMeeting_NotMember(t *testing.T) {
 func TestTeamsMeeting_TooManyMembers(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice"), indMember("bob"), indMember("carol")}, nil)
@@ -538,7 +538,7 @@ func TestTeamsMeeting_TooManyMembers(t *testing.T) {
 func TestTeamsMeeting_GraphCreateFails(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r1", nil, nil, false).
 		Return([]model.RoomMember{indMember("alice")}, nil)
@@ -557,7 +557,7 @@ func TestTeamsMeeting_GraphCreateFails(t *testing.T) {
 func TestTeamsMeeting_RecordReadFails(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").Return(&model.Subscription{RoomID: "r1"}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").Return(nil)
 	store.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel}, nil)
 
 	graph := &fakeGraphClient{}
diff --git a/room-service/handler_test.go b/room-service/handler_test.go
index ff11365ca..4b6718447 100644
--- a/room-service/handler_test.go
+++ b/room-service/handler_test.go
@@ -1075,7 +1075,7 @@ func TestHandler_AddMembers_SilentlyFiltersBotsFromChannelRefs(t *testing.T) {
 
 	// Channel-ref expansion: same-site source channel returns a human + a bot.
 	srcRef := model.ChannelRef{RoomID: "r_src", SiteID: "site-a"}
-	store.EXPECT().GetSubscription(gomock.Any(), "alice", "r_src").Return(&model.Subscription{}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), "alice", "r_src").Return(nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), "r_src", gomock.Any(), nil, false).Return([]model.RoomMember{
 		{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "bob"}},
 		{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "weather.bot"}},
@@ -1347,7 +1347,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch1", gomock.Any(), nil, false).Return([]model.RoomMember{
 			{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "bob"}},
 			{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "carol"}},
@@ -1367,7 +1367,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch1", gomock.Any(), nil, false).Return([]model.RoomMember{
 			{Member: model.RoomMemberEntry{ID: "org1", Type: model.RoomMemberOrg}},
 			{Member: model.RoomMemberEntry{ID: "org2", Type: model.RoomMemberOrg}},
@@ -1387,7 +1387,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch1", gomock.Any(), nil, false).Return([]model.RoomMember{
 			{Member: model.RoomMemberEntry{ID: "org1", Type: model.RoomMemberOrg}},
 			{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "bob"}},
@@ -1429,7 +1429,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		local := model.ChannelRef{RoomID: "ch-local", SiteID: "site-a"}
 		remote := model.ChannelRef{RoomID: "ch-remote", SiteID: "site-eu"}
 
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch-local").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch-local").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch-local", gomock.Any(), nil, false).Return([]model.RoomMember{
 			{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "local-user"}},
 		}, nil)
@@ -1450,7 +1450,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(nil, model.ErrSubscriptionNotFound)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(model.ErrSubscriptionNotFound)
 
 		h := &Handler{store: store, siteID: "site-a", maxRoomSize: 1000, memberListClient: mc}
 		_, _, err := h.expandChannelRefs(context.Background(), "alice", []model.ChannelRef{ch})
@@ -1465,7 +1465,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(nil, errors.New("mongo timeout"))
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(errors.New("mongo timeout"))
 
 		h := &Handler{store: store, siteID: "site-a", maxRoomSize: 1000, memberListClient: mc}
 		_, _, err := h.expandChannelRefs(context.Background(), "alice", []model.ChannelRef{ch})
@@ -1480,8 +1480,8 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch-slow", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch-slow").
-			Return(nil, context.DeadlineExceeded)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch-slow").
+			Return(context.DeadlineExceeded)
 
 		h := &Handler{store: store, siteID: "site-a", maxRoomSize: 1000, memberListClient: mc, memberListTimeout: 10 * time.Millisecond}
 		_, _, err := h.expandChannelRefs(context.Background(), "alice", []model.ChannelRef{ch})
@@ -1520,7 +1520,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch1", gomock.Any(), nil, false).Return(nil, errors.New("mongo timeout"))
 
 		h := &Handler{store: store, siteID: "site-a", maxRoomSize: 1000, memberListClient: mc}
@@ -1620,7 +1620,7 @@ func TestHandler_AddMembers_ChannelExpansion(t *testing.T) {
 		mc := NewMockMemberListClient(ctrl)
 
 		ch := model.ChannelRef{RoomID: "ch1", SiteID: "site-a"}
-		store.EXPECT().GetSubscription(gomock.Any(), "alice", "ch1").Return(&model.Subscription{}, nil)
+		store.EXPECT().CheckMembership(gomock.Any(), "alice", "ch1").Return(nil)
 		store.EXPECT().ListRoomMembers(gomock.Any(), "ch1", gomock.Any(), nil, false).Return([]model.RoomMember{
 			{Member: model.RoomMemberEntry{ID: "unknown", Type: ""}},
 			{Member: model.RoomMemberEntry{Type: model.RoomMemberIndividual, Account: "bob"}},
@@ -1663,8 +1663,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "happy path returns members",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().ListRoomMembers(gomock.Any(), roomID, (*int)(nil), (*int)(nil), false).
 					Return([]model.RoomMember{orgMember, existingMember}, nil)
 			},
@@ -1678,8 +1678,8 @@ func TestHandler_ListMembers(t *testing.T) {
 					ID: "sub-xyz", RoomID: roomID, Ts: time.Unix(3, 0).UTC(),
 					Member: model.RoomMemberEntry{ID: "u-alice", Type: model.RoomMemberIndividual, Account: "alice"},
 				}
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().ListRoomMembers(gomock.Any(), roomID, (*int)(nil), (*int)(nil), false).
 					Return([]model.RoomMember{synth}, nil)
 			},
@@ -1692,8 +1692,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "requester not a member",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
 			},
 			want: want{errIs: errNotRoomMember},
 		},
@@ -1701,8 +1701,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "invalid JSON body",
 			body: []byte("{not json"),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 			},
 			want: want{errContains: "invalid request"},
 		},
@@ -1710,8 +1710,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "non-positive limit: negative",
 			body: []byte(`{"limit":-1}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 			},
 			want: want{errContains: "limit must be > 0"},
 		},
@@ -1719,8 +1719,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "non-positive limit: zero",
 			body: []byte(`{"limit":0}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 			},
 			want: want{errContains: "limit must be > 0"},
 		},
@@ -1728,8 +1728,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "negative offset",
 			body: []byte(`{"offset":-1}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 			},
 			want: want{errContains: "offset must be >= 0"},
 		},
@@ -1737,8 +1737,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "pagination passed through",
 			body: []byte(`{"limit":10,"offset":5}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().ListRoomMembers(gomock.Any(), roomID, gomock.Any(), gomock.Any(), false).
 					DoAndReturn(func(_ context.Context, _ string, limit, offset *int, _ bool) ([]model.RoomMember, error) {
 						require.NotNil(t, limit)
@@ -1754,8 +1754,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "auth probe infra error",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("mongo exploded"))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("mongo exploded"))
 			},
 			want: want{errContains: "check room membership"},
 		},
@@ -1763,8 +1763,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "store error on list",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().ListRoomMembers(gomock.Any(), roomID, (*int)(nil), (*int)(nil), false).
 					Return(nil, fmt.Errorf("mongo exploded"))
 			},
@@ -1774,8 +1774,8 @@ func TestHandler_ListMembers(t *testing.T) {
 			name: "enrich=true passed through to store",
 			body: []byte(`{"enrich":true}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().ListRoomMembers(gomock.Any(), roomID, (*int)(nil), (*int)(nil), true).
 					Return([]model.RoomMember{
 						{
@@ -1837,8 +1837,8 @@ func TestHandler_ListMembers_EmptyBody(t *testing.T) {
 	)
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-		Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+		Return(nil)
 	store.EXPECT().ListRoomMembers(gomock.Any(), roomID, (*int)(nil), (*int)(nil), false).
 		Return([]model.RoomMember{{ID: "rm1", RoomID: roomID, Member: model.RoomMemberEntry{ID: "alice", Type: model.RoomMemberIndividual, Account: "alice"}}}, nil)
 
@@ -3053,8 +3053,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "happy path",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, account, true, nil)
 				s.store.EXPECT().ListReadReceipts(gomock.Any(), roomID, createdAt, account, gomock.Any()).
@@ -3072,8 +3072,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "empty readers",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, account, true, nil)
 				s.store.EXPECT().ListReadReceipts(gomock.Any(), roomID, createdAt, account, gomock.Any()).
@@ -3090,8 +3090,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "not a room member",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(nil, model.ErrSubscriptionNotFound)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(model.ErrSubscriptionNotFound)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, account, true, nil).AnyTimes()
 			},
@@ -3101,8 +3101,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "message not found",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return("", time.Time{}, "", false, nil)
 			},
@@ -3112,8 +3112,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "message in another room",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return("other-room", createdAt, account, true, nil)
 			},
@@ -3123,8 +3123,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "not the sender",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, "bob", true, nil)
 			},
@@ -3134,8 +3134,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "store error on subscription",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(nil, fmt.Errorf("db down"))
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(fmt.Errorf("db down"))
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, account, true, nil).AnyTimes()
 			},
@@ -3145,8 +3145,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "store error on message lookup",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return("", time.Time{}, "", false, fmt.Errorf("cass down"))
 			},
@@ -3156,8 +3156,8 @@ func TestHandler_handleMessageReadReceipt(t *testing.T) {
 			name: "store error on aggregation",
 			req:  req,
 			prep: func(s setup) {
-				s.store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				s.store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				s.reader.EXPECT().GetMessageRoomAndCreatedAt(gomock.Any(), messageID).
 					Return(roomID, createdAt, account, true, nil)
 				s.store.EXPECT().ListReadReceipts(gomock.Any(), roomID, createdAt, account, gomock.Any()).
@@ -3335,17 +3335,6 @@ func baseThreadSub(account, roomID, parent, threadRoomID string) *model.ThreadSu
 	}
 }
 
-func baseSubForThreadRead(account, roomID string, threadUnread []string, alert bool) *model.Subscription {
-	return &model.Subscription{
-		User:         model.SubscriptionUser{ID: "u-" + account, Account: account},
-		RoomID:       roomID,
-		SiteID:       "site-a",
-		JoinedAt:     time.Now().UTC().Add(-time.Hour),
-		ThreadUnread: threadUnread,
-		Alert:        alert,
-	}
-}
-
 func TestHandler_MessageThreadRead_EmptyThreadID(t *testing.T) {
 	f := newThreadReadFixture(t)
 	_, err := f.handler.messageThreadRead(ctxParams(map[string]string{"account": "alice", "roomID": "r1"}), model.MessageThreadReadRequest{ThreadID: ""})
@@ -3354,8 +3343,8 @@ func TestHandler_MessageThreadRead_EmptyThreadID(t *testing.T) {
 
 func TestHandler_MessageThreadRead_NotRoomMember(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(nil, model.ErrSubscriptionNotFound)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(model.ErrSubscriptionNotFound)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil).AnyTimes()
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("site-a", nil).AnyTimes()
@@ -3367,8 +3356,8 @@ func TestHandler_MessageThreadRead_NotRoomMember(t *testing.T) {
 
 func TestHandler_MessageThreadRead_ThreadSubNotFound(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(nil, model.ErrThreadSubscriptionNotFound)
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("site-a", nil).AnyTimes()
@@ -3386,8 +3375,8 @@ func TestHandler_MessageThreadRead_ThreadSubNotFound(t *testing.T) {
 // Simulate by returning context.Canceled on the siblings.
 func TestHandler_MessageThreadRead_ThreadSubNotFound_SiblingsCancelled(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(nil, context.Canceled).AnyTimes()
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(context.Canceled).AnyTimes()
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(nil, model.ErrThreadSubscriptionNotFound)
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").
@@ -3400,8 +3389,8 @@ func TestHandler_MessageThreadRead_ThreadSubNotFound_SiblingsCancelled(t *testin
 func TestHandler_MessageThreadRead_BothMiss_RoomNotMemberWins(t *testing.T) {
 	for i := 0; i < 20; i++ {
 		f := newThreadReadFixture(t)
-		f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-			Return(nil, model.ErrSubscriptionNotFound)
+		f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+			Return(model.ErrSubscriptionNotFound)
 		f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 			Return(nil, model.ErrThreadSubscriptionNotFound).AnyTimes()
 		f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("site-a", nil).AnyTimes()
@@ -3414,8 +3403,8 @@ func TestHandler_MessageThreadRead_BothMiss_RoomNotMemberWins(t *testing.T) {
 func TestHandler_MessageThreadRead_HappyAlertClears(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3433,8 +3422,8 @@ func TestHandler_MessageThreadRead_HappyAlertClears(t *testing.T) {
 func TestHandler_MessageThreadRead_HappyAlertStays(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1", "p2"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3450,8 +3439,8 @@ func TestHandler_MessageThreadRead_HappyAlertStays(t *testing.T) {
 func TestHandler_MessageThreadRead_IdempotentIDNotInArray(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p2"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3467,8 +3456,8 @@ func TestHandler_MessageThreadRead_IdempotentIDNotInArray(t *testing.T) {
 func TestHandler_MessageThreadRead_AlertAlreadyFalse(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, false), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3484,8 +3473,8 @@ func TestHandler_MessageThreadRead_AlertAlreadyFalse(t *testing.T) {
 func TestHandler_MessageThreadRead_CrossSite_PublishesOutbox(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1", "p2"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3521,8 +3510,8 @@ func TestHandler_MessageThreadRead_CrossSite_PublishesOutbox(t *testing.T) {
 func TestHandler_MessageThreadRead_GetUserSiteID_Empty(t *testing.T) {
 	f := newThreadReadFixture(t)
 	withNopFloor(f)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", gomock.Any()).
@@ -3538,8 +3527,8 @@ func TestHandler_MessageThreadRead_GetUserSiteID_Empty(t *testing.T) {
 
 func TestHandler_MessageThreadRead_GetUserSiteID_Error(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("", fmt.Errorf("boom"))
@@ -3557,8 +3546,8 @@ func TestHandler_MessageThreadRead_GetUserSiteID_Error(t *testing.T) {
 func TestHandler_MessageThreadRead_OutboxPublishError(t *testing.T) {
 	f := newThreadReadFixture(t)
 	f.publishCallErr = fmt.Errorf("nats down")
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", gomock.Any()).
@@ -3574,8 +3563,8 @@ func TestHandler_MessageThreadRead_OutboxPublishError(t *testing.T) {
 
 func TestHandler_MessageThreadRead_UpdateSubscriptionError(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("site-a", nil)
@@ -3591,8 +3580,8 @@ func TestHandler_MessageThreadRead_UpdateSubscriptionError(t *testing.T) {
 
 func TestHandler_MessageThreadRead_UpdateThreadSubscriptionError(t *testing.T) {
 	f := newThreadReadFixture(t)
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(baseThreadSub("alice", "r1", "p1", "tr1"), nil)
 	f.store.EXPECT().GetUserSiteID(gomock.Any(), "alice").Return("site-a", nil)
@@ -3619,8 +3608,8 @@ func baseThreadRoomForFloor(threadRoomID string) *model.ThreadRoom {
 }
 
 func fullThreadReadSetup(f *threadReadFixture, tsub *model.ThreadSubscription) {
-	f.store.EXPECT().GetSubscription(gomock.Any(), "alice", "r1").
-		Return(baseSubForThreadRead("alice", "r1", []string{"p1"}, true), nil)
+	f.store.EXPECT().CheckMembership(gomock.Any(), "alice", "r1").
+		Return(nil)
 	f.store.EXPECT().GetThreadSubscriptionByParent(gomock.Any(), "alice", "p1", "r1").
 		Return(tsub, nil)
 	f.store.EXPECT().UpdateSubscriptionThreadRead(gomock.Any(), "r1", "alice", "p1").
@@ -3951,8 +3940,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "current version, happy path",
 			body: []byte(`{}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().Get(gomock.Any(), roomID).Return(sampleVersioned, nil)
 			},
 			want: want{replyJSON: `{"roomId":"room-1","version":7,"privateKey":"QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkI="}`},
@@ -3961,8 +3950,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "explicit version, happy path",
 			body: []byte(`{"version":3}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().GetByVersion(gomock.Any(), roomID, 3).Return(&sampleKey, nil)
 			},
 			want: want{replyJSON: `{"roomId":"room-1","version":3,"privateKey":"QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkI="}`},
@@ -3971,8 +3960,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "not a member",
 			body: []byte(`{}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(nil, model.ErrSubscriptionNotFound)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(model.ErrSubscriptionNotFound)
 			},
 			want: want{errSubstr: "only room members"},
 		},
@@ -3980,8 +3969,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "current key absent",
 			body: []byte(`{}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().Get(gomock.Any(), roomID).Return(nil, nil)
 			},
 			want: want{errSubstr: "room key not available"},
@@ -3990,8 +3979,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "historical version absent",
 			body: []byte(`{"version":1}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().GetByVersion(gomock.Any(), roomID, 1).Return(nil, nil)
 			},
 			want: want{errSubstr: "room key not available"},
@@ -4000,8 +3989,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "store error",
 			body: []byte(`{}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().Get(gomock.Any(), roomID).Return(nil, errors.New("valkey down"))
 			},
 			want: want{errSubstr: "get room key:"},
@@ -4010,8 +3999,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "store error on explicit version",
 			body: []byte(`{"version":5}`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 				ks.EXPECT().GetByVersion(gomock.Any(), roomID, 5).Return(nil, errors.New("valkey down"))
 			},
 			want: want{errSubstr: "get room key:"},
@@ -4020,8 +4009,8 @@ func TestHandler_natsGetRoomKey(t *testing.T) {
 			name: "malformed body",
 			body: []byte(`not-json`),
 			setup: func(t *testing.T, store *MockRoomStore, ks *MockRoomKeyStore) {
-				store.EXPECT().GetSubscription(gomock.Any(), account, roomID).
-					Return(&model.Subscription{}, nil)
+				store.EXPECT().CheckMembership(gomock.Any(), account, roomID).
+					Return(nil)
 			},
 			want: want{errSubstr: "invalid request"},
 		},
@@ -4067,7 +4056,7 @@ func TestHandler_GetRoomKey_EmptyBody(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	store := NewMockRoomStore(ctrl)
 	ks := NewMockRoomKeyStore(ctrl)
-	store.EXPECT().GetSubscription(gomock.Any(), account, roomID).Return(&model.Subscription{}, nil)
+	store.EXPECT().CheckMembership(gomock.Any(), account, roomID).Return(nil)
 	ks.EXPECT().Get(gomock.Any(), roomID).Return(sampleVersioned, nil)
 
 	h := NewHandler(store, ks, nil, nil, siteID, 1000, 500, 5*time.Second, 5, nil, nil, nil, 0)
@@ -4275,7 +4264,7 @@ func TestHandleRoomRestricted_Validation(t *testing.T) {
 			setupStore: func(s *MockRoomStore) {
 				s.EXPECT().GetUser(gomock.Any(), "admin1").Return(&model.User{Account: "admin1", Roles: []model.UserRole{model.UserRoleAdmin}}, nil)
 				s.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel, Restricted: true, UserCount: 10}, nil)
-				s.EXPECT().GetSubscription(gomock.Any(), "nonmember", "r1").Return(nil, mongo.ErrNoDocuments)
+				s.EXPECT().CheckMembership(gomock.Any(), "nonmember", "r1").Return(model.ErrSubscriptionNotFound)
 			},
 			wantErr: errOwnerNotMember,
 		},
@@ -4299,7 +4288,7 @@ func TestHandleRoomRestricted_Validation(t *testing.T) {
 			setupStore: func(s *MockRoomStore) {
 				s.EXPECT().GetUser(gomock.Any(), "admin1").Return(&model.User{Account: "admin1", Roles: []model.UserRole{model.UserRoleAdmin}}, nil)
 				s.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel, Restricted: false, UserCount: 3}, nil)
-				s.EXPECT().GetSubscription(gomock.Any(), "owner1", "r1").Return(&model.Subscription{}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), "owner1", "r1").Return(nil)
 			},
 			wantErr: errNotEnoughMembers,
 		},
@@ -4312,7 +4301,7 @@ func TestHandleRoomRestricted_Validation(t *testing.T) {
 			setupStore: func(s *MockRoomStore) {
 				s.EXPECT().GetUser(gomock.Any(), "admin1").Return(&model.User{Account: "admin1", Roles: []model.UserRole{model.UserRoleAdmin}}, nil)
 				s.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel, Restricted: false, UserCount: 10}, nil)
-				s.EXPECT().GetSubscription(gomock.Any(), "owner1", "r1").Return(&model.Subscription{}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), "owner1", "r1").Return(nil)
 				happyPathRestrictedSuccessSetup(s)
 			},
 			wantErr: nil,
@@ -4338,7 +4327,7 @@ func TestHandleRoomRestricted_Validation(t *testing.T) {
 			setupStore: func(s *MockRoomStore) {
 				s.EXPECT().GetUser(gomock.Any(), "admin1").Return(&model.User{Account: "admin1", Roles: []model.UserRole{model.UserRoleAdmin}}, nil)
 				s.EXPECT().GetRoom(gomock.Any(), "r1").Return(&model.Room{ID: "r1", Type: model.RoomTypeChannel, Restricted: true, UserCount: 2}, nil)
-				s.EXPECT().GetSubscription(gomock.Any(), "owner2", "r1").Return(&model.Subscription{}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), "owner2", "r1").Return(nil)
 				happyPathRestrictedSuccessSetup(s)
 			},
 			wantErr: nil,
@@ -4394,8 +4383,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "default limit 3, happy path",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 				s.EXPECT().ListMemberStatuses(gomock.Any(), roomID, 3).Return(stub, nil)
@@ -4410,8 +4399,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "nil limit clamped to small UserCount",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 2}, nil)
 				s.EXPECT().ListMemberStatuses(gomock.Any(), roomID, 2).Return(stub, nil)
@@ -4425,8 +4414,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "nil limit + empty room returns empty without store call",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 0}, nil)
 			},
@@ -4436,8 +4425,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "explicit limit passes through",
 			body: []byte(`{"limit":7}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 				s.EXPECT().ListMemberStatuses(gomock.Any(), roomID, 7).Return(stub, nil)
@@ -4452,8 +4441,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "requester not a member",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil).AnyTimes()
 			},
@@ -4468,8 +4457,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "not-member takes precedence over GetRoom error",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(nil, fmt.Errorf("mongo exploded"))
 			},
@@ -4479,8 +4468,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "GetSubscription infra error",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("mongo exploded"))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("mongo exploded"))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil).AnyTimes()
 			},
@@ -4490,8 +4479,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "limit zero",
 			body: []byte(`{"limit":0}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 			},
 			want: want{errIs: errMemberStatusesLimitInvalid},
@@ -4500,8 +4489,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "limit negative",
 			body: []byte(`{"limit":-1}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 			},
 			want: want{errIs: errMemberStatusesLimitInvalid},
@@ -4510,8 +4499,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "limit exceeds room.UserCount",
 			body: []byte(`{"limit":11}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 			},
 			want: want{errIs: errMemberStatusesLimitInvalid},
@@ -4520,8 +4509,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "limit equal to room.UserCount is valid",
 			body: []byte(`{"limit":10}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 				s.EXPECT().ListMemberStatuses(gomock.Any(), roomID, 10).Return(stub, nil)
 			},
@@ -4531,8 +4520,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "GetRoom errors",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(nil, fmt.Errorf("mongo exploded"))
 			},
 			want: want{errContains: "get room"},
@@ -4541,8 +4530,8 @@ func TestHandler_ListMemberStatuses(t *testing.T) {
 			name: "store errors",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(&model.Room{ID: roomID, UserCount: 10}, nil)
 				s.EXPECT().ListMemberStatuses(gomock.Any(), roomID, 3).
 					Return(nil, fmt.Errorf("mongo exploded"))
@@ -5491,8 +5480,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "default limit 3, empty filter, happy path",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 				s.EXPECT().
@@ -5508,8 +5497,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "nil limit clamped to small UserCount+AppCount",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 1, AppCount: 1}, nil)
 				s.EXPECT().
@@ -5523,8 +5512,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "nil limit + empty room returns empty without store call",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 0, AppCount: 0}, nil)
 			},
@@ -5534,8 +5523,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "explicit limit and filter passed through",
 			body: []byte(`{"limit":3,"filter":"bo"}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 				s.EXPECT().
@@ -5548,8 +5537,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "regex metacharacters in filter are escaped",
 			body: []byte(`{"limit":3,"filter":"a.b(c"}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 				s.EXPECT().
@@ -5566,8 +5555,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "requester not a member",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil).AnyTimes()
 			},
@@ -5582,8 +5571,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "not-member takes precedence over GetRoom error",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("missing: %w", model.ErrSubscriptionNotFound))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(nil, fmt.Errorf("mongo exploded"))
 			},
@@ -5593,8 +5582,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "GetSubscription infra error",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(nil, fmt.Errorf("mongo exploded"))
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(fmt.Errorf("mongo exploded"))
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil).AnyTimes()
 			},
@@ -5604,8 +5593,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "limit zero",
 			body: []byte(`{"limit":0}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 			},
@@ -5615,8 +5604,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "limit negative",
 			body: []byte(`{"limit":-1}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 			},
@@ -5626,8 +5615,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "limit exceeds UserCount + AppCount",
 			body: []byte(`{"limit":8}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 			},
@@ -5637,8 +5626,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "limit at cap is accepted",
 			body: []byte(`{"limit":7}`),
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 				s.EXPECT().
@@ -5651,8 +5640,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "GetRoom errors",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).Return(nil, fmt.Errorf("mongo exploded"))
 			},
 			want: want{errContains: "get room"},
@@ -5661,8 +5650,8 @@ func TestHandler_ListMentionableSubscriptions(t *testing.T) {
 			name: "store errors",
 			body: nil,
 			setupMock: func(s *MockRoomStore) {
-				s.EXPECT().GetSubscription(gomock.Any(), requester, roomID).
-					Return(&model.Subscription{User: model.SubscriptionUser{Account: requester}, RoomID: roomID}, nil)
+				s.EXPECT().CheckMembership(gomock.Any(), requester, roomID).
+					Return(nil)
 				s.EXPECT().GetRoom(gomock.Any(), roomID).
 					Return(&model.Room{ID: roomID, UserCount: 5, AppCount: 2}, nil)
 				s.EXPECT().
diff --git a/room-service/integration_test.go b/room-service/integration_test.go
index 6568c491d..daa96cf18 100644
--- a/room-service/integration_test.go
+++ b/room-service/integration_test.go
@@ -128,6 +128,94 @@ func TestMongoStore_Integration(t *testing.T) {
 	assert.Error(t, err, "expected error for missing subscription")
 }
 
+// TestMongoStore_CheckMembership_Integration verifies the projected existence
+// check: nil when subscribed, model.ErrSubscriptionNotFound when not.
+func TestMongoStore_CheckMembership_Integration(t *testing.T) {
+	ctx := context.Background()
+	db := setupMongo(t)
+	store := NewMongoStore(db)
+
+	mustInsertSub(t, db, &model.Subscription{
+		ID:     "s1",
+		User:   model.SubscriptionUser{ID: "u1", Account: "alice"},
+		RoomID: "r1",
+		Roles:  []model.Role{model.RoleMember},
+	})
+
+	assert.NoError(t, store.CheckMembership(ctx, "alice", "r1"))
+
+	err := store.CheckMembership(ctx, "bob", "r1")
+	assert.ErrorIs(t, err, model.ErrSubscriptionNotFound)
+
+	err = store.CheckMembership(ctx, "alice", "r2")
+	assert.ErrorIs(t, err, model.ErrSubscriptionNotFound)
+}
+
+// TestMongoStore_GetRoom_ProjectionFields_Integration pins the field set that
+// GetRoom's projection must return: every Room field read by any handler call
+// site. Dropping one from the projection would silently zero it here, so this
+// test is the guard for the projected read path.
+func TestMongoStore_GetRoom_ProjectionFields_Integration(t *testing.T) {
+	ctx := context.Background()
+	db := setupMongo(t)
+	store := NewMongoStore(db)
+
+	lastMsg := time.Now().UTC().Add(-time.Hour).Truncate(time.Millisecond)
+	minSeen := time.Now().UTC().Add(-2 * time.Hour).Truncate(time.Millisecond)
+	mustInsertRoom(t, db, &model.Room{
+		ID: "rproj", Name: "proj-room", Type: model.RoomTypeChannel, SiteID: "site-a",
+		UserCount: 7, AppCount: 3, Restricted: true, ExternalAccess: true,
+		LastMsgAt: &lastMsg, MinUserLastSeenAt: &minSeen, LastMsgID: "m123",
+	})
+
+	got, err := store.GetRoom(ctx, "rproj")
+	require.NoError(t, err)
+	assert.Equal(t, "rproj", got.ID)
+	assert.Equal(t, "proj-room", got.Name)
+	assert.Equal(t, model.RoomTypeChannel, got.Type)
+	assert.Equal(t, 7, got.UserCount)
+	assert.Equal(t, 3, got.AppCount)
+	assert.True(t, got.Restricted)
+	assert.True(t, got.ExternalAccess)
+	require.NotNil(t, got.LastMsgAt)
+	assert.WithinDuration(t, lastMsg, *got.LastMsgAt, time.Second)
+	require.NotNil(t, got.MinUserLastSeenAt)
+	assert.WithinDuration(t, minSeen, *got.MinUserLastSeenAt, time.Second)
+}
+
+// TestMongoStore_GetSubscription_ProjectionFields_Integration pins the field
+// set that GetSubscription's projection must return: every Subscription field
+// read by any handler call site. Same guard rationale as the GetRoom variant.
+func TestMongoStore_GetSubscription_ProjectionFields_Integration(t *testing.T) {
+	ctx := context.Background()
+	db := setupMongo(t)
+	store := NewMongoStore(db)
+
+	lastSeen := time.Now().UTC().Add(-30 * time.Minute).Truncate(time.Millisecond)
+	mustInsertSub(t, db, &model.Subscription{
+		ID:           "sproj",
+		User:         model.SubscriptionUser{ID: "u9", Account: "carol", IsBot: true},
+		RoomID:       "rproj",
+		SiteID:       "site-a",
+		Roles:        []model.Role{model.RoleOwner, model.RoleMember},
+		Alert:        true,
+		ThreadUnread: []string{"t1", "t2"},
+		LastSeenAt:   &lastSeen,
+	})
+
+	got, err := store.GetSubscription(ctx, "carol", "rproj")
+	require.NoError(t, err)
+	assert.Equal(t, "u9", got.User.ID)
+	assert.Equal(t, "carol", got.User.Account)
+	assert.Equal(t, "rproj", got.RoomID)
+	assert.Equal(t, "site-a", got.SiteID)
+	assert.Equal(t, []model.Role{model.RoleOwner, model.RoleMember}, got.Roles)
+	assert.True(t, got.Alert)
+	assert.Equal(t, []string{"t1", "t2"}, got.ThreadUnread)
+	require.NotNil(t, got.LastSeenAt)
+	assert.WithinDuration(t, lastSeen, *got.LastSeenAt, time.Second)
+}
+
 func TestMongoStore_GetSubscriptionWithMembership_Integration(t *testing.T) {
 	db := setupMongo(t)
 	store := NewMongoStore(db)
@@ -2336,9 +2424,9 @@ func TestMongoStore_ToggleSubscriptionMute(t *testing.T) {
 	assert.Equal(t, "alice", got.User.Account)
 	assert.Equal(t, "r1", got.RoomID)
 
-	persisted, err := store.GetSubscription(ctx, "alice", "r1")
-	require.NoError(t, err)
-	assert.True(t, persisted.Muted)
+	// muted is not projected by GetSubscription (no handler reads it from a read
+	// result), so verify persistence with a direct field read.
+	assert.True(t, subBoolField(t, db, "r1", "alice", "muted"))
 	// muteUpdatedAt is stamped at the supplied instant (BSON ms precision) so the
 	// origin doc shares the federated event's high-water mark.
 	assert.Equal(t, ts1.UnixMilli(), subTimeField(t, db, "r1", "alice", "muteUpdatedAt").UnixMilli())
@@ -2371,6 +2459,22 @@ func subTimeField(t *testing.T, db *mongo.Database, roomID, account, field strin
 	return dt.Time().UTC()
 }
 
+// subBoolField reads a boolean field straight from the stored subscription
+// document. Used to assert persistence of fields (muted, favorite) that
+// GetSubscription deliberately does not project, so the read-back cannot rely
+// on the projected struct.
+func subBoolField(t *testing.T, db *mongo.Database, roomID, account, field string) bool {
+	t.Helper()
+	var doc bson.M
+	require.NoError(t, db.Collection("subscriptions").
+		FindOne(context.Background(), bson.M{"roomId": roomID, "u.account": account}).Decode(&doc))
+	v, ok := doc[field]
+	require.True(t, ok, "field %q missing on subscription", field)
+	b, ok := v.(bool)
+	require.True(t, ok, "field %q is %T, want bool", field, v)
+	return b
+}
+
 func TestMongoStore_ToggleSubscriptionFavorite(t *testing.T) {
 	db := testutil.MongoDB(t, "room-svc-fav")
 	store := NewMongoStore(db)
@@ -2400,9 +2504,9 @@ func TestMongoStore_ToggleSubscriptionFavorite(t *testing.T) {
 	assert.Equal(t, "alice", got.User.Account)
 	assert.Equal(t, "r1", got.RoomID)
 
-	persisted, err := store.GetSubscription(ctx, "alice", "r1")
-	require.NoError(t, err)
-	assert.True(t, persisted.Favorite)
+	// favorite is not projected by GetSubscription (no handler reads it from a
+	// read result), so verify persistence with a direct field read.
+	assert.True(t, subBoolField(t, db, "r1", "alice", "favorite"))
 	// favoriteUpdatedAt is stamped at the supplied instant so the origin doc
 	// shares the federated event's high-water mark.
 	assert.Equal(t, ts1.UnixMilli(), subTimeField(t, db, "r1", "alice", "favoriteUpdatedAt").UnixMilli())
diff --git a/room-service/mock_store_test.go b/room-service/mock_store_test.go
index 5955585aa..16a84de64 100644
--- a/room-service/mock_store_test.go
+++ b/room-service/mock_store_test.go
@@ -57,6 +57,20 @@ func (mr *MockRoomStoreMockRecorder) ApplySubscriptionVisibility(ctx, roomID, re
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ApplySubscriptionVisibility", reflect.TypeOf((*MockRoomStore)(nil).ApplySubscriptionVisibility), ctx, roomID, restricted, externalAccess, ownerAccount, visibilityUpdatedAt)
 }
 
+// CheckMembership mocks base method.
+func (m *MockRoomStore) CheckMembership(ctx context.Context, account, roomID string) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "CheckMembership", ctx, account, roomID)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// CheckMembership indicates an expected call of CheckMembership.
+func (mr *MockRoomStoreMockRecorder) CheckMembership(ctx, account, roomID any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CheckMembership", reflect.TypeOf((*MockRoomStore)(nil).CheckMembership), ctx, account, roomID)
+}
+
 // CountMembersAndOwners mocks base method.
 func (m *MockRoomStore) CountMembersAndOwners(ctx context.Context, roomID string) (*RoomCounts, error) {
 	m.ctrl.T.Helper()
diff --git a/room-service/store.go b/room-service/store.go
index adca03570..e978daeac 100644
--- a/room-service/store.go
+++ b/room-service/store.go
@@ -64,6 +64,13 @@ type RoomStore interface {
 	ListRoomsByIDs(ctx context.Context, ids []string) ([]model.Room, error)
 	GetThreadUnreadSummary(ctx context.Context, account, siteID string) (*ThreadUnreadSummary, error)
 	GetSubscription(ctx context.Context, account, roomID string) (*model.Subscription, error)
+	// CheckMembership verifies (account, roomID) has a subscription without
+	// decoding the document — an {_id:1}-projected existence check for the
+	// many call sites that only need the membership gate, not the sub's fields.
+	// Returns nil when subscribed, model.ErrSubscriptionNotFound (wrapped) when
+	// not, or a wrapped infra error otherwise. Same error contract as
+	// GetSubscription so callers branch identically on errors.Is.
+	CheckMembership(ctx context.Context, account, roomID string) error
 	// ListMemberStatuses returns up to `limit` members of roomID, each
 	// projected from the corresponding users document as {account, engName,
 	// chineseName, statusIsShow, statusText}. Subscriptions whose user
diff --git a/room-service/store_mongo.go b/room-service/store_mongo.go
index 8baf95cb9..35ca7d9cf 100644
--- a/room-service/store_mongo.go
+++ b/room-service/store_mongo.go
@@ -238,9 +238,34 @@ func (s *MongoStore) InsertTeamsMeeting(ctx context.Context, record model.TeamsM
 	return nil
 }
 
+// roomReadProjection is the field set GetRoom returns — the union of every
+// Room field read by a handler call site. The full Room doc is never needed on
+// these read paths, and projecting trims the BSON decode (a top CPU consumer in
+// profiling) plus the wire payload. Keep in sync with the Room field reads in
+// handler.go; the projection-field integration test guards drift.
+var roomReadProjection = bson.D{
+	{Key: "_id", Value: 1}, {Key: "type", Value: 1}, {Key: "name", Value: 1},
+	{Key: "userCount", Value: 1}, {Key: "appCount", Value: 1},
+	{Key: "restricted", Value: 1}, {Key: "externalAccess", Value: 1},
+	{Key: "lastMsgAt", Value: 1}, {Key: "minUserLastSeenAt", Value: 1},
+}
+
+// subscriptionReadProjection is the field set GetSubscription returns — the
+// union of every Subscription field read by a handler call site. The fat
+// Subscription doc (~30 fields incl. byte arrays and time pointers) is never
+// needed here; projecting trims the reflection-heavy BSON decode. Keep in sync
+// with the Subscription field reads in handler.go; the projection-field
+// integration test guards drift.
+var subscriptionReadProjection = bson.D{
+	{Key: "_id", Value: 1}, {Key: "u", Value: 1}, {Key: "roomId", Value: 1},
+	{Key: "siteId", Value: 1}, {Key: "roles", Value: 1}, {Key: "alert", Value: 1},
+	{Key: "threadUnread", Value: 1}, {Key: "lastSeenAt", Value: 1},
+}
+
 func (s *MongoStore) GetRoom(ctx context.Context, id string) (*model.Room, error) {
 	var room model.Room
-	if err := s.rooms.FindOne(ctx, bson.M{"_id": id}).Decode(&room); err != nil {
+	opts := options.FindOne().SetProjection(roomReadProjection)
+	if err := s.rooms.FindOne(ctx, bson.M{"_id": id}, opts).Decode(&room); err != nil {
 		return nil, fmt.Errorf("room %q not found: %w", id, err)
 	}
 	return &room, nil
@@ -249,7 +274,8 @@ func (s *MongoStore) GetRoom(ctx context.Context, id string) (*model.Room, error
 func (s *MongoStore) GetSubscription(ctx context.Context, account, roomID string) (*model.Subscription, error) {
 	var sub model.Subscription
 	filter := bson.M{"u.account": account, "roomId": roomID}
-	if err := s.subscriptions.FindOne(ctx, filter).Decode(&sub); err != nil {
+	opts := options.FindOne().SetProjection(subscriptionReadProjection)
+	if err := s.subscriptions.FindOne(ctx, filter, opts).Decode(&sub); err != nil {
 		if errors.Is(err, mongo.ErrNoDocuments) {
 			return nil, fmt.Errorf("%q in room %q: %w", account, roomID, model.ErrSubscriptionNotFound)
 		}
@@ -258,6 +284,23 @@ func (s *MongoStore) GetSubscription(ctx context.Context, account, roomID string
 	return &sub, nil
 }
 
+// membershipExistsProjection returns only _id so the existence check decodes
+// essentially nothing — the cheapest form of GetSubscription for call sites
+// that use the result solely as a membership gate.
+var membershipExistsProjection = bson.D{{Key: "_id", Value: 1}}
+
+func (s *MongoStore) CheckMembership(ctx context.Context, account, roomID string) error {
+	filter := bson.M{"u.account": account, "roomId": roomID}
+	opts := options.FindOne().SetProjection(membershipExistsProjection)
+	if err := s.subscriptions.FindOne(ctx, filter, opts).Err(); err != nil {
+		if errors.Is(err, mongo.ErrNoDocuments) {
+			return fmt.Errorf("%q in room %q: %w", account, roomID, model.ErrSubscriptionNotFound)
+		}
+		return fmt.Errorf("check membership for %q in room %q: %w", account, roomID, err)
+	}
+	return nil
+}
+
 // GetSubscriptionWithMembership loads the target subscription joined with their
 // individual and org membership sources. Used by the remove-member validation
 // flow to decide whether a user can leave or be removed individually.