diff --git a/reputation/types.proto b/reputation/types.proto
index 87690d6..5939537 100644
--- a/reputation/types.proto
+++ b/reputation/types.proto
@@ -5,13 +5,28 @@ package neo.fs.v2.reputation;
 option go_package = "github.com/nspcc-dev/neofs-api-go/v2/reputation/grpc;reputation";
 option csharp_namespace = "Neo.FileStorage.API.Reputation";
 
+// NeoFS unique peer identifier.
+//
+// `PeerID` is a 33 byte long compressed public key of the node
+// stored in network map.
+//
+// String presentation is
+// [base58](https://tools.ietf.org/html/draft-msporny-base58-02) encoded string.
+//
+// JSON value will be the data encoded as a string using standard base64
+// encoding with paddings. Either
+// [standard](https://tools.ietf.org/html/rfc4648#section-4) or
+// [URL-safe](https://tools.ietf.org/html/rfc4648#section-5) base64 encoding
+// with/without paddings are accepted.
+message PeerID {
+    // Peer identifier in a binary format.
+    bytes value = 1 [json_name = "value"];
+}
+
 // Trust value to NeoFS network peer.
 message Trust {
     // Identifier of the trusted peer.
-    //
-    // For storage nodes, it is the node's public key
-    // fixed in the network map.
-    bytes peer = 1 [json_name = "peer"];
+    PeerID peer = 1 [json_name = "peer"];
 
     // Trust value.
     double value = 2 [json_name = "value"];