diff --git a/shared/util/codeql/util/AlertFiltering.qll b/shared/util/codeql/util/AlertFiltering.qll
index 6ca62e50af2..e7c01807e6f 100644
--- a/shared/util/codeql/util/AlertFiltering.qll
+++ b/shared/util/codeql/util/AlertFiltering.qll
@@ -6,22 +6,31 @@
 private import codeql.util.Location
 
 /**
- * Restricts alerts to a specific location in specific files.
+ * Holds if the query should produce alerts that match the given line ranges.
  *
- * If this predicate is empty, accept all alerts. Otherwise, accept alerts only at the specified
- * locations. Note that alert restrictions apply only to the start line of an alert (even if the
- * alert location spans multiple lines) because alerts are displayed on their start lines.
+ * This predicate is active if and only if it is nonempty. If this predicate is inactive, it has no
+ * effect. If it is active, it accepts any alert that has at least one matching location.
  *
- * - filePath: Absolute path of the file to restrict alerts to.
- * - startLine: Start line number (starting with 1, inclusive) to restrict alerts to.
- * - endLine: End line number (starting with 1, inclusive) to restrict alerts to.
+ * Note that an alert that is not accepted by this filtering predicate may still be included in the
+ * query results if it is accepted by another active filtering predicate in this module. An alert is
+ * excluded from the query results if only if (1) there is at least one active filtering predicate,
+ * and (2) it is not accepted by any active filtering predicate.
  *
- * If startLine and endLine are both 0, accept alerts anywhere in the file.
+ * An alert location is a match if it matches a row in this predicate. If `startLineStart` and
+ * `startLineEnd` are both 0, the row specifies a whole-file match, and a location is a match if
+ * its file path matches `filePath`. Otherwise, the row specifies a line-range match, and a
+ * location is a match if its file path matches `filePath`, and its start line is between
+ * `startLineStart` and `startLineEnd`, inclusive. (Note that only start line of the location is
+ * used for matching because an alert is displayed on the first line of its location.)
  *
- * A query should either completely ignore this predicate (i.e., perform no filtering whatsoever),
- * or only return alerts that meet the filtering criteria as specified above.
+ * - filePath: alert location file path (absolute).
+ * - startLineStart: inclusive start of the range for alert location start line number (1-based).
+ * - startLineEnd: inclusive end of the range for alert location start line number (1-based).
+ *
+ * A query should either perform no alert filtering, or adhere to all the filtering rules in this
+ * module and return all and only the accepted alerts.
  */
-extensible predicate restrictAlertsTo(string filePath, int startLine, int endLine);
+extensible predicate restrictAlertsTo(string filePath, int startLineStart, int startLineEnd);
 
 /** Module for applying alert location filtering. */
 module AlertFilteringImpl<LocationSig Location> {
@@ -30,14 +39,14 @@ module AlertFilteringImpl<LocationSig Location> {
   predicate filterByLocation(Location location) {
     not restrictAlertsTo(_, _, _)
     or
-    exists(string filePath, int startLine, int endLine |
-      restrictAlertsTo(filePath, startLine, endLine)
+    exists(string filePath, int startLineStart, int startLineEnd |
+      restrictAlertsTo(filePath, startLineStart, startLineEnd)
     |
-      startLine = 0 and
-      endLine = 0 and
+      startLineStart = 0 and
+      startLineEnd = 0 and
       location.hasLocationInfo(filePath, _, _, _, _)
       or
-      location.hasLocationInfo(filePath, [startLine .. endLine], _, _, _)
+      location.hasLocationInfo(filePath, [startLineStart .. startLineEnd], _, _, _)
     )
   }
 }