diff --git a/packages/core/src/utils/RelationQueries.ts b/packages/core/src/utils/RelationQueries.ts
index a2a5e20de..36f248ef0 100644
--- a/packages/core/src/utils/RelationQueries.ts
+++ b/packages/core/src/utils/RelationQueries.ts
@@ -17,19 +17,19 @@ type CamelCaseIdObject<T extends string> = KeysToCamelCase<{
   [Key in `${T}_id`]: string;
 }>;
 
-class RelationQueryError extends Error {}
-
 /**
  * Query class for relation tables that connect several tables by their entry ids.
  *
- * @example
  * Let's say we have two tables `users` and `groups` and a relation table
  * `user_group_relations`. Then we can create a `RelationQueries` instance like this:
  *
  * ```ts
- * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', 'users', 'groups');
+ * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', Users, Groups);
  * ```
  *
+ * `Users` and `Groups` are the schemas of the tables that satisfy the {@link TableInfo}
+ * interface. The generated schemas in `@logto/schemas` satisfy this interface.
+ *
  * To insert a new relation, we can use the {@link RelationQueries.insert} method:
  *
  * ```ts
@@ -44,7 +44,7 @@ class RelationQueryError extends Error {}
  * To get all entries for a specific table, we can use the {@link RelationQueries.getEntries} method:
  *
  * ```ts
- * await userGroupRelations.getEntries('users', { group_id: 'group-id-1' });
+ * await userGroupRelations.getEntries(Users, { groupId: 'group-id-1' });
  * ```
  *
  * This will return all entries for the `users` table that are connected to the
@@ -63,7 +63,8 @@ export default class RelationQueries<
   /**
    * @param pool The database pool.
    * @param relationTable The name of the relation table.
-   * @param relations The names of the tables that are connected by the relation table.
+   * @param relations The schemas of the tables that are connected by the relation table.
+   * @see {@link TableInfo} for more information about the schemas.
    */
   constructor(
     public readonly pool: CommonQueryMethods,
@@ -81,7 +82,7 @@ export default class RelationQueries<
    *
    * @example
    * ```ts
-   * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', 'users', 'groups');
+   * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', Users, Groups);
    *
    * userGroupRelations.insert(['user-id-1', 'group-id-1']);
    * // Insert multiple relations at once
@@ -113,6 +114,19 @@ export default class RelationQueries<
     `);
   }
 
+  /**
+   * Delete a relation from the relation table.
+   *
+   * @param data The ids of the entries to delete. The keys must be in camel case
+   * and end with `Id`.
+   * @returns A Promise that resolves to the query result.
+   *
+   * @example
+   * ```ts
+   * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', Users, Groups);
+   * userGroupRelations.delete({ userId: 'user-id-1', groupId: 'group-id-1' });
+   * ```
+   */
   async delete(data: CamelCaseIdObject<Schemas[number]['tableSingular']>) {
     const snakeCaseData = snakecaseKeys(data);
     return this.pool.query(sql`
@@ -126,6 +140,21 @@ export default class RelationQueries<
     `);
   }
 
+  /**
+   * Get all entries for a specific schema that are connected to the given ids.
+   *
+   * @param forSchema The schema to get the entries for.
+   * @param where Other ids to filter the entries by. The keys must be in camel case
+   * and end with `Id`.
+   * @returns A Promise that resolves an array of entries of the given schema.
+   *
+   * @example
+   * ```ts
+   * const userGroupRelations = new RelationQueries(pool, 'user_group_relations', Users, Groups);
+   *
+   * userGroupRelations.getEntries(Users, { groupId: 'group-id-1' });
+   * ```
+   */
   async getEntries<S extends Schemas[number]>(
     forSchema: S,
     where: CamelCaseIdObject<Exclude<Schemas[number]['tableSingular'], S['tableSingular']>>