diff --git a/proto/controlclient.proto b/proto/controlclient.proto
index acf726f..bc38199 100644
--- a/proto/controlclient.proto
+++ b/proto/controlclient.proto
@@ -21,21 +21,29 @@ service ScsControl {
   rpc ListIndexes(_ListIndexesRequest) returns (_ListIndexesResponse) {}
 }
 
-message _CreateIndexRequest {
-  message _EuclideanSimilarity{}
+message _SimilarityMetric {
+  message _EuclideanSimilarity {
+  }
 
-  message _InnerProduct{}
+  message _InnerProduct {
+  }
+
+  message _CosineSimilarity {
+  }
 
-  message _CosineSimilarity{}
-  string index_name = 1;
-  uint64 num_dimensions = 2;
   oneof similarity_metric {
-    _EuclideanSimilarity euclidean_similarity = 3;
-    _InnerProduct inner_product = 4;
-    _CosineSimilarity cosine_similarity = 5;
+    _EuclideanSimilarity euclidean_similarity = 1;
+    _InnerProduct inner_product = 2;
+    _CosineSimilarity cosine_similarity = 3;
   }
 }
 
+message _CreateIndexRequest {
+  string index_name = 1;
+  uint64 num_dimensions = 2;
+  _SimilarityMetric similarity_metric = 3;
+}
+
 message _CreateIndexResponse {
 }
 
@@ -50,7 +58,12 @@ message _ListIndexesRequest {
 }
 
 message _ListIndexesResponse {
-  repeated string index_names = 1;
+  message _Index {
+    string index_name = 1;
+    uint64 num_dimensions = 2;
+    _SimilarityMetric similarity_metric = 3;
+  }
+  repeated _Index indexes = 1;
 }
 
 message _DeleteCacheRequest {