diff --git a/lib/src/repository.rs b/lib/src/repository.rs
index b9f92cf6..2ee0ad10 100644
--- a/lib/src/repository.rs
+++ b/lib/src/repository.rs
@@ -85,7 +85,7 @@ pub trait RepositoryConnection: Clone {
     /// ```
     fn prepare_query<'a>(&'a self, query: &str, base_iri: Option<&'a str>) -> Result<Self::PreparedQuery>;
 
-
+    /// This is similar to `prepare_query`, but useful if a SPARQL query has already been parsed, which is the case when building `ServiceHandler`s for federated queries with `SERVICE` clauses. For examples, look in the tests.
     fn prepare_query_from_pattern<'a>(
         &'a self,
         graph_pattern: &'a GraphPattern,
diff --git a/lib/src/sparql/eval.rs b/lib/src/sparql/eval.rs
index 61dd9e61..989dcb90 100644
--- a/lib/src/sparql/eval.rs
+++ b/lib/src/sparql/eval.rs
@@ -1662,6 +1662,7 @@ impl<'a, S: StoreConnection + 'a> SimpleEvaluator<S> {
         )
     }
 
+    // this is used to encode results froma BindingIterator into an EncodedTuplesIterator. This happens when SERVICE clauses are evaluated
     fn encode_bindings<'b>(
         &'b self,
         variables: &'b [Variable],
diff --git a/lib/src/sparql/mod.rs b/lib/src/sparql/mod.rs
index 93bc6156..5593b3b7 100644
--- a/lib/src/sparql/mod.rs
+++ b/lib/src/sparql/mod.rs
@@ -117,6 +117,7 @@ impl<'a, S: StoreConnection + 'a> SimplePreparedQuery<S> {
         }))
     }
 
+    /// Builds SimplePreparedQuery from an existing `GraphPattern`. This is used to support federated queries via `SERVICE` clauses
     pub(crate) fn new_from_pattern(
         connection: S,
         pattern: &GraphPattern,