diff --git a/discoveryapis_generator/lib/discoveryapis_generator.dart b/discoveryapis_generator/lib/discoveryapis_generator.dart
index 23b2a572f..e30591413 100644
--- a/discoveryapis_generator/lib/discoveryapis_generator.dart
+++ b/discoveryapis_generator/lib/discoveryapis_generator.dart
@@ -5,6 +5,8 @@
 import 'dart:convert';
 import 'dart:io';
 
+import 'package:path/path.dart' as path;
+
 import 'src/apis_files_generator.dart';
 import 'src/apis_package_generator.dart';
 import 'src/generated_googleapis/discovery/v1.dart';
@@ -40,11 +42,20 @@ List<GenerateResult> generateAllLibraries(
   Pubspec pubspec, {
   bool deleteExisting = true,
   required Set<String> skipTests,
+  Set<String>? knownApis,
 }) {
   final apiDescriptions = Directory(inputDirectory)
       .listSync()
       .whereType<File>()
-      .where((fse) => fse.path.endsWith('.json'))
+      .where((fse) {
+        final isApiFile = fse.path.endsWith('.json');
+        final filename = path.basenameWithoutExtension(fse.path);
+        if (knownApis != null) {
+          final apiName = filename.replaceAll('__', ':');
+          return knownApis.contains(apiName) && isApiFile;
+        }
+        return isApiFile;
+      })
       .map((entity) => RestDescription.fromJson(
             json.decode(entity.readAsStringSync()) as Map,
           ))
diff --git a/generator/lib/src/package_configuration.dart b/generator/lib/src/package_configuration.dart
index 756afa2c2..70ba30e64 100644
--- a/generator/lib/src/package_configuration.dart
+++ b/generator/lib/src/package_configuration.dart
@@ -46,6 +46,7 @@ class DiscoveryPackagesConfiguration {
   late final Set<String> excessApis;
   late final List<String> missingApis;
   late final Set<String> skipTests;
+  late final Set<String> knownApis;
   final existingApiRevisions = <String, String>{};
   Map<String?, String>? newRevisions;
   Map<String?, String>? oldRevisions;
@@ -178,6 +179,7 @@ class DiscoveryPackagesConfiguration {
         package.pubspec,
         deleteExisting: deleteExisting,
         skipTests: skipTests,
+        knownApis: knownApis,
       );
       for (final result in results) {
         if (!result.success) {
@@ -209,7 +211,7 @@ class DiscoveryPackagesConfiguration {
     packages =
         _packagesFromYaml(yaml['packages'] as YamlList, configFile, allApis);
     skipTests = _listFromYaml(yaml['skip_tests'] as YamlList?).toSet();
-    final knownApis = _calculateKnownApis(
+    knownApis = _calculateKnownApis(
       packages,
       _listFromYaml(yaml['skipped_apis'] as YamlList?),
     );