diff --git a/core/src/main/java/hudson/scm/SCM.java b/core/src/main/java/hudson/scm/SCM.java
index 4994febe4b679742c16d2db44c91bed40364a968..297ec0e2e14f663f5384783b252aff642551a57f 100644
--- a/core/src/main/java/hudson/scm/SCM.java
+++ b/core/src/main/java/hudson/scm/SCM.java
@@ -700,7 +700,10 @@ public abstract class SCM implements Describable<SCM>, ExtensionPoint {
     }
 
     /**
-     * Returns the list of {@link SCMDescriptor}s that are applicable to the given project.
+     * Determines which kinds of SCMs are applicable to a given project.
+     * @param project a project on which we might be configuring SCM, or null if unknown
+     * @return all descriptors which {@link SCMDescriptor#isApplicable(Job)} to it, also filtered by {@link TopLevelItemDescriptor#isApplicable};
+     *         or simply {@link #all} if there is no project
      * @since 1.568
      */
     public static List<SCMDescriptor<?>> _for(@CheckForNull final Job project) {