diff --git a/test/README.md b/test/README.md
index c05bf247..00eb1f60 100644
--- a/test/README.md
+++ b/test/README.md
@@ -1,9 +1,25 @@
-# Integration Tests
+# Integration and Live Tests
 
-The integration tests will run against the live GitHub API. These tests will
-verify that the library is properly coded against the actual behavior of the
-GitHub API.
+## Unit and Contract Tests
 
+All unit tests, contract tests, security tests, and model tests run offline without external dependencies:
+
+```bash
+dart test
+```
+
+## Safe Live Smoke Tests
+
+Safe read-only smoke tests are located in `test/live/smoke_test.dart`.
+These tests only perform safe, non-destructive read operations against public GitHub endpoints:
+
+```bash
+GITHUB_LIVE_SMOKE=1 dart test test/live/smoke_test.dart
+```
+
+## Destructive Integration Tests
+
+The legacy integration tests run against the live GitHub API with write operations.
 To run these tests a GitHub repository and OAuth token will need to be defined
 in the `config/config.dart` file.
 
diff --git a/test/live/smoke_test.dart b/test/live/smoke_test.dart
new file mode 100644
index 00000000..8fe46813
--- /dev/null
+++ b/test/live/smoke_test.dart
@@ -0,0 +1,57 @@
+import 'dart:io';
+
+import 'package:github/github.dart';
+import 'package:test/test.dart';
+
+/// Opt-in safe live smoke test suite.
+///
+/// Runs only when GITHUB_TOKEN or GITHUB_LIVE_SMOKE=1 is set in the environment.
+/// Executes only safe, non-destructive read operations against public GitHub endpoints.
+void main() {
+  final hasToken = Platform.environment.containsKey('GITHUB_TOKEN') ||
+      Platform.environment['GITHUB_LIVE_SMOKE'] == '1';
+
+  group('Live GitHub API Smoke Tests (Read-Only)', () {
+    late GitHub github;
+
+    setUp(() {
+      final token = Platform.environment['GITHUB_TOKEN'];
+      github = GitHub(
+        auth: token != null
+            ? Authentication.withToken(token)
+            : const Authentication.anonymous(),
+      );
+    });
+
+    tearDown(() {
+      github.dispose();
+    });
+
+    test('fetches public repository metadata', () async {
+      final repo = await github.repositories
+          .getRepository(RepositorySlug('octocat', 'Hello-World'));
+
+      expect(repo.name, equals('Hello-World'));
+      expect(repo.owner?.login, equals('octocat'));
+    });
+
+    test('fetches API status from status endpoint', () async {
+      final status = await github.misc.getApiStatus();
+      expect(status.status, isNotNull);
+      expect(status.status?.indicator, isNotNull);
+    });
+
+    test('fetches zen message', () async {
+      final zen = await github.misc.getZen();
+      expect(zen, isNotEmpty);
+    });
+
+    test('fetches gitignore templates list', () async {
+      final templates = await github.misc.listGitignoreTemplates();
+      expect(templates, contains('Dart'));
+    });
+  },
+      skip: !hasToken
+          ? 'Skipped: Set GITHUB_TOKEN or GITHUB_LIVE_SMOKE=1 to run safe live tests.'
+          : null);
+}
diff --git a/test/unit/browser_auth_test.dart b/test/unit/browser_auth_test.dart
new file mode 100644
index 00000000..3f45ca61
--- /dev/null
+++ b/test/unit/browser_auth_test.dart
@@ -0,0 +1,37 @@
+@TestOn('chrome')
+library;
+
+// ignore: deprecated_member_use
+import 'dart:html';
+
+import 'package:github/src/browser/xplat_browser.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('Browser Authentication', () {
+    tearDown(() {
+      window.sessionStorage.clear();
+    });
+
+    test('loads token from sessionStorage by default', () {
+      window.sessionStorage['GITHUB_TOKEN'] = 'session-pat-12345';
+      final auth = findAuthenticationFromEnvironment();
+      expect(auth.isAnonymous, isFalse);
+      expect(auth.token, equals('session-pat-12345'));
+    });
+
+    test('ignores query string by default even if present in URL', () {
+      // By default allowQueryAuth is false
+      final auth = findAuthenticationFromEnvironment();
+      // Unless present in sessionStorage, it should default to anonymous
+      expect(auth.isAnonymous, isTrue);
+    });
+
+    test('returns anonymous auth when neither sessionStorage nor query present',
+        () {
+      window.sessionStorage.clear();
+      final auth = findAuthenticationFromEnvironment();
+      expect(auth.isAnonymous, isTrue);
+    });
+  });
+}
diff --git a/tool/coverage_check.dart b/tool/coverage_check.dart
new file mode 100644
index 00000000..bbff09d9
--- /dev/null
+++ b/tool/coverage_check.dart
@@ -0,0 +1,55 @@
+import 'dart:io';
+
+/// Validates that test coverage meets or exceeds the required floor.
+///
+/// Usage: dart run tool/coverage_check.dart [coverage_file_or_dir] [--min=percentage]
+void main(List<String> args) {
+  var minCoverage = 50.0;
+  String? targetPath;
+
+  for (final arg in args) {
+    if (arg.startsWith('--min=')) {
+      minCoverage = double.parse(arg.substring(6));
+    } else if (!arg.startsWith('--')) {
+      targetPath = arg;
+    }
+  }
+
+  targetPath ??= 'coverage/lcov.info';
+  final file = File(targetPath);
+
+  if (!file.existsSync()) {
+    print('Coverage file not found at $targetPath. Skipping coverage check.');
+    exit(0);
+  }
+
+  final lines = file.readAsLinesSync();
+  var linesFound = 0;
+  var linesHit = 0;
+
+  for (final line in lines) {
+    if (line.startsWith('LF:')) {
+      linesFound += int.tryParse(line.substring(3).trim()) ?? 0;
+    } else if (line.startsWith('LH:')) {
+      linesHit += int.tryParse(line.substring(3).trim()) ?? 0;
+    }
+  }
+
+  if (linesFound == 0) {
+    print('No executable lines found in $targetPath.');
+    exit(0);
+  }
+
+  final percentage = (linesHit / linesFound) * 100.0;
+  print(
+      'Test line coverage: ${percentage.toStringAsFixed(2)}% ($linesHit / $linesFound lines hit)');
+  print('Required coverage floor: ${minCoverage.toStringAsFixed(2)}%');
+
+  if (percentage < minCoverage) {
+    print(
+        'Error: Coverage ${percentage.toStringAsFixed(2)}% is below required floor of ${minCoverage.toStringAsFixed(2)}%!');
+    exit(1);
+  }
+
+  print('Coverage check passed successfully.');
+}