diff --git a/ql/src/codeql_ruby/Diagnostics.qll b/ql/src/codeql_ruby/Diagnostics.qll
index e2e28a84b07..d97030b57e7 100644
--- a/ql/src/codeql_ruby/Diagnostics.qll
+++ b/ql/src/codeql_ruby/Diagnostics.qll
@@ -47,9 +47,6 @@ class Diagnostic extends @diagnostic {
 }
 
 /** A diagnostic relating to a particular error in extracting a file. */
-class ExtractionError extends Diagnostic {
-  ExtractionError() {
-    this.getSeverity() = 3 and
-    this.getTag() = "parse_error"
-  }
+class ExtractionError extends Diagnostic, @diagnostic_error {
+  ExtractionError() { this.getTag() = "parse_error" }
 }