diff --git a/roomserver/storage/interface.go b/roomserver/storage/interface.go
index 57058748e..149d5849b 100644
--- a/roomserver/storage/interface.go
+++ b/roomserver/storage/interface.go
@@ -28,6 +28,7 @@ import (
 )
 
 type Database interface {
+	UserRoomKeys
 	// Do we support processing input events for more than one room at a time?
 	SupportsConcurrentRoomInputs() bool
 	// RoomInfo returns room information for the given room ID, or nil if there is no room.
@@ -193,15 +194,23 @@ type Database interface {
 	MaybeRedactEvent(
 		ctx context.Context, roomInfo *types.RoomInfo, eventNID types.EventNID, event gomatrixserverlib.PDU, plResolver state.PowerLevelResolver,
 	) (gomatrixserverlib.PDU, gomatrixserverlib.PDU, error)
+}
 
+type UserRoomKeys interface {
+	// InsertUserRoomPrivatePublicKey inserts the given private key as well as the public key for it. This should be used
+	// when creating keys locally.
 	InsertUserRoomPrivatePublicKey(ctx context.Context, userID spec.UserID, roomID spec.RoomID, key ed25519.PrivateKey) (result ed25519.PrivateKey, err error)
-	SelectUserRoomPrivateKey(ctx context.Context, userID spec.UserID, roomID spec.RoomID) (key ed25519.PrivateKey, err error)
+	// InsertUserRoomPublicKey inserts the given public key, this should be used for users NOT local to this server
 	InsertUserRoomPublicKey(ctx context.Context, userID spec.UserID, roomID spec.RoomID, key ed25519.PublicKey) (result ed25519.PublicKey, err error)
+	// SelectUserRoomPrivateKey selects the private key for the given user and room combination
+	SelectUserRoomPrivateKey(ctx context.Context, userID spec.UserID, roomID spec.RoomID) (key ed25519.PrivateKey, err error)
+	// SelectUserIDsForPublicKeys selects all userIDs for the requested senderKeys. Returns a map from roomID -> map from publicKey to userID
 	SelectUserIDsForPublicKeys(ctx context.Context, publicKeys map[spec.RoomID][]ed25519.PublicKey) (map[spec.RoomID]map[string]string, error)
 }
 
 type RoomDatabase interface {
 	EventDatabase
+	UserRoomKeys
 	// RoomInfo returns room information for the given room ID, or nil if there is no room.
 	RoomInfo(ctx context.Context, roomID string) (*types.RoomInfo, error)
 	RoomInfoByNID(ctx context.Context, roomNID types.RoomNID) (*types.RoomInfo, error)
diff --git a/roomserver/storage/tables/interface.go b/roomserver/storage/tables/interface.go
index 1f1e433af..8f2422a32 100644
--- a/roomserver/storage/tables/interface.go
+++ b/roomserver/storage/tables/interface.go
@@ -186,9 +186,14 @@ type Purge interface {
 }
 
 type UserRoomKeys interface {
+	// InsertUserRoomPrivatePublicKey inserts the given private key as well as the public key for it. This should be used
+	// when creating keys locally.
 	InsertUserRoomPrivatePublicKey(ctx context.Context, txn *sql.Tx, userNID types.EventStateKeyNID, roomNID types.RoomNID, key ed25519.PrivateKey) (ed25519.PrivateKey, error)
+	// InsertUserRoomPublicKey inserts the given public key, this should be used for users NOT local to this server
 	InsertUserRoomPublicKey(ctx context.Context, txn *sql.Tx, userNID types.EventStateKeyNID, roomNID types.RoomNID, key ed25519.PublicKey) (ed25519.PublicKey, error)
+	// SelectUserRoomPrivateKey selects the private key for the given user and room combination
 	SelectUserRoomPrivateKey(ctx context.Context, txn *sql.Tx, userNID types.EventStateKeyNID, roomNID types.RoomNID) (ed25519.PrivateKey, error)
+	// BulkSelectUserNIDs selects all userIDs for the requested senderKeys. Returns a map from publicKey -> types.UserRoomKeyPair.
 	BulkSelectUserNIDs(ctx context.Context, txn *sql.Tx, senderKeys map[types.RoomNID][]ed25519.PublicKey) (map[string]types.UserRoomKeyPair, error)
 }