diff --git a/src/libstore/build/goal.hh b/src/libstore/build/goal.hh
index a313bf22c..d3127caea 100644
--- a/src/libstore/build/goal.hh
+++ b/src/libstore/build/goal.hh
@@ -162,6 +162,10 @@ public:
 
     virtual void cleanup() { }
 
+    /**
+     * @brief Hint for the scheduler, which concurrency limit applies.
+     * @see JobCategory
+     */
     virtual JobCategory jobCategory() = 0;
 };