diff --git a/core/src/main/java/hudson/scm/SCM.java b/core/src/main/java/hudson/scm/SCM.java
index 4c9f7b0ec8605d3c84cca04f06f5abf915bf8552..73711dd4cbd0a2fe353569de5ebf63184ab6be2f 100644
--- a/core/src/main/java/hudson/scm/SCM.java
+++ b/core/src/main/java/hudson/scm/SCM.java
@@ -523,9 +523,9 @@ public abstract class SCM implements Describable<SCM>, ExtensionPoint {
      *
      * <p>
      * This method is invoked whenever someone does {@link AbstractBuild#getEnvironment(TaskListener)}, via
-     * {@link #buildEnvVars(AbstractBuild, Map)}, whichvcan be before/after your checkout method is invoked. So if you
-     * are going to provide information aboutvcheck out (like SVN revision number that was checked out), be prepared
-     * for the possibility that thevcheck out hasn't happened yet.
+     * {@link #buildEnvVars(AbstractBuild, Map)}, which can be before/after your checkout method is invoked. So if you
+     * are going to provide information about check out (like SVN revision number that was checked out), be prepared
+     * for the possibility that the check out hasn't happened yet.
      *
      * @since FIXME
      */
diff --git a/core/src/main/java/jenkins/scm/RunWithSCM.java b/core/src/main/java/jenkins/scm/RunWithSCM.java
index c16e52dca041941847049e14a5bc59142aa80cbb..1189e56de910c4a13709bd012113602d4a451cef 100644
--- a/core/src/main/java/jenkins/scm/RunWithSCM.java
+++ b/core/src/main/java/jenkins/scm/RunWithSCM.java
@@ -47,7 +47,7 @@ import java.util.logging.Logger;
 
 /**
  * Allows a {@link Run} to provide {@link SCM}-related methods, such as providing changesets and culprits.
- * 
+ *
  * @since FIXME
  */
 public interface RunWithSCM<JobT extends Job<JobT, RunT> & Queue.Task,
@@ -64,7 +64,8 @@ public interface RunWithSCM<JobT extends Job<JobT, RunT> & Queue.Task,
     /**
      * Gets the ids for all {@link User}s included in {@link #getChangeSets()} for this item.
      *
-     * @return A possibly null set of user IDs.
+     * @return A set of user IDs, or null if this was the first time the method was called or the build is still running
+     * for a {@link RunWithSCM} instance with no culprits.
      */
     @CheckForNull
     Set<String> getCulpritIds();
@@ -110,7 +111,7 @@ public interface RunWithSCM<JobT extends Job<JobT, RunT> & Queue.Task,
     }
 
     /**
-     * Internal method used for actually calculating the culprits from scratch. Called by {@link #getCulprits()} and
+     * Method used for actually calculating the culprits from scratch. Called by {@link #getCulprits()} and
      * overrides of {@link #getCulprits()}. Does not persist culprits information.
      *
      * @return a non-null {@link Set} of {@link User}s associated with this item.