diff --git a/src/traft/mod.rs b/src/traft/mod.rs
index 8b04d489ee86d74f71e260b7b762cf0390d1d58b..107d5ceb1614a0a3af8286379bfa63ffc626d978 100644
--- a/src/traft/mod.rs
+++ b/src/traft/mod.rs
@@ -154,7 +154,8 @@ pub struct Peer {
     pub replicaset_id: String,
     pub replicaset_uuid: String,
 
-    /// Index in the raft log. `0` means it's not committed yet.
+    /// Index of the most recent raft log entry that persisted this peer.
+    /// `0` means it's not committed yet.
     pub commit_index: u64,
 
     /// The state of this instance's activity.