feat: improve doc comments

crates/store/src/db/mod.rs

@@ -163,6 +163,7 @@ impl Db {
         })?
     }
 
+    /// Loads the nullifiers that match the prefixes from the DB.
     pub async fn select_nullifiers_by_prefix(
         &self,
         prefix_len: u32,
@@ -171,7 +172,9 @@ impl Db {
         self.pool
             .get()
             .await?
-            .interact(move |conn| sql::select_nullifiers_by_prefix(conn, prefix_len, &nullifier_prefixes))
+            .interact(move |conn| {
+                sql::select_nullifiers_by_prefix(conn, prefix_len, &nullifier_prefixes)
+            })
             .await
             .map_err(|err| {
                 DatabaseError::InteractError(format!(

crates/store/src/db/sql.rs

@@ -307,6 +307,17 @@ pub fn select_nullifiers_by_block_range(
     Ok(result)
 }
 
+/// Select nullifiers created that match the `nullifier_prefixes` filter using the given
+/// [Connection].
+///
+/// Each value of the `nullifier_prefixes` is only the `prefix_len` most significant bits
+/// of the nullifier of interest to the client. This hides the details of the specific
+/// nullifier being requested.
+///
+/// # Returns
+///
+/// A vector of [NullifierInfo] with the nullifiers and the block height at which they were
+/// created, or an error.
 pub fn select_nullifiers_by_prefix(
     conn: &mut Connection,
     _prefix_len: u32,

crates/store/src/server/api.rs

@@ -110,6 +110,9 @@ impl api_server::Api for StoreApi {
         Ok(Response::new(CheckNullifiersResponse { proofs: convert(proofs) }))
     }
 
+    /// Returns nullifiers that match the specified prefixes and have been consumed.
+    ///
+    /// Currently the only supported prefix length is 16 bits.
     #[instrument(
         target = "miden-store",
         name = "store:check_nullifiers_by_prefix",

proto/requests.proto

@@ -10,9 +10,9 @@ message ApplyBlockRequest {
     bytes block = 1;
 }
 
-// Returns a list of nullifiers recorded in the node
+// Returns a list of nullifiers that match the specified prefixes and are recorded in the node.
 message CheckNullifiersByPrefixRequest {
-    // Number of bits used for nullifier prefix.
+    // Number of bits used for nullifier prefix. Currently the only supported value is 16.
     uint32 prefix_len = 1;
     // List of nullifiers to check. Each nullifier is specified by its prefix with length equal
     // to prefix_len