diff --git a/buf.yaml b/buf.yaml
index c186e1eb9be1d4a89fef6fe6b101d3497f7bd662..57d0c99f3996e730f83971c4b7b0d2626b848ea7 100644
--- a/buf.yaml
+++ b/buf.yaml
@@ -8,7 +8,6 @@ lint:
     - DEFAULT
     - COMMENTS
     - OTHER
-    - UNARY_RPC
   except:
   ignore:
 breaking:
diff --git a/proto/caosdb/entity/v1alpha1/main.proto b/proto/caosdb/entity/v1alpha1/main.proto
index 7406dee978fdbe94630b796b3ef92dc2088aed0a..435b4f0a9a4adaf96f46fb8f5d230b65382631f6 100644
--- a/proto/caosdb/entity/v1alpha1/main.proto
+++ b/proto/caosdb/entity/v1alpha1/main.proto
@@ -552,6 +552,8 @@ message EntityResponse {
 message IdResponse {
   // The entity id.
   string id = 1;
+  // The entity version.
+  Version version = 5;
   // Errors for this entity which occurred during the current transaction. The
   // presence of errors indicates that a transaction was not successful and the
   // errors describe why this is the case.
@@ -742,27 +744,6 @@ message MultiTransactionResponse {
   repeated Message transaction_infos = 4;
 }
 
-// Wraps multiple sub-transaction requests of mixed types.
-message MultiTransactionRequest {
-  // The actual payload.
-  repeated TransactionRequest requests = 1;
-}
-
-// A response containing only the id (of a deleted, inserted, or updated
-// entity) and the usual trias of entity messages.
-message IdResponse {
-  // The entity id.
-  string id = 1;
-  // The entity version.
-  Version version = 5;
-  // Entity errors.
-  repeated Message entity_errors = 2;
-  // Entity warnings.
-  repeated Message entity_warnings = 3;
-  // Entity info messages.
-  repeated Message entity_infos = 4;
-}
-
 // Entity Transaction Service
 service EntityTransactionService {
   // Issue multiple mixed requests