diff --git a/lib/App/registerContainer.php b/lib/App/registerContainer.php
index 4ef62d1..b58eaf3 100644
--- a/lib/App/registerContainer.php
+++ b/lib/App/registerContainer.php
@@ -12,9 +12,13 @@ use MintyPHP\App\Container\Registrars\SettingsRegistrar;
 use MintyPHP\App\Container\Registrars\UserRegistrar;
 use MintyPHP\App\Module\ModuleEventDispatcher;
 use MintyPHP\App\Module\ModuleRegistry;
+use MintyPHP\Service\Audit\ApiAuditServiceInterface;
+use MintyPHP\Service\Audit\ApiSystemAuditReporterInterface;
 use MintyPHP\Service\Audit\AuditMetadataEnricherInterface;
 use MintyPHP\Service\Audit\AuditRecorderInterface;
 use MintyPHP\Service\Audit\ImportAuditInterface;
+use MintyPHP\Service\Audit\NullApiAuditService;
+use MintyPHP\Service\Audit\NullApiSystemAuditReporter;
 use MintyPHP\Service\Audit\NullAuditMetadataEnricher;
 use MintyPHP\Service\Audit\NullAuditRecorder;
 use MintyPHP\Service\Audit\NullImportAudit;
@@ -87,5 +91,11 @@ if (!$container->has(ImportAuditInterface::class)) {
 if (!$container->has(AuditMetadataEnricherInterface::class)) {
     $container->set(AuditMetadataEnricherInterface::class, static fn (): AuditMetadataEnricherInterface => new NullAuditMetadataEnricher());
 }
+if (!$container->has(ApiAuditServiceInterface::class)) {
+    $container->set(ApiAuditServiceInterface::class, static fn (): ApiAuditServiceInterface => new NullApiAuditService());
+}
+if (!$container->has(ApiSystemAuditReporterInterface::class)) {
+    $container->set(ApiSystemAuditReporterInterface::class, static fn (): ApiSystemAuditReporterInterface => new NullApiSystemAuditReporter());
+}
 
 return $container;
diff --git a/lib/Console/Runner/Doctor/DoctorRunner.php b/lib/Console/Runner/Doctor/DoctorRunner.php
index 2570a9e..a23b21e 100644
--- a/lib/Console/Runner/Doctor/DoctorRunner.php
+++ b/lib/Console/Runner/Doctor/DoctorRunner.php
@@ -8,10 +8,10 @@ use MintyPHP\App\AppContainer;
 use MintyPHP\App\Bootstrap\EnvValidator;
 use MintyPHP\Console\Support\CliAppBootstrap;
 use MintyPHP\DB;
-use MintyPHP\Module\Audit\Service\SystemAuditService;
 use MintyPHP\Service\Access\AuthorizationService;
 use MintyPHP\Service\Access\PermissionService;
 use MintyPHP\Service\Access\UiAccessService;
+use MintyPHP\Service\Audit\AuditRecorderInterface;
 use MintyPHP\Service\Auth\AuthService;
 use Throwable;
 
@@ -283,7 +283,7 @@ final class DoctorRunner implements DoctorRunnerInterface
         $durationMs = max(0, (int) round((microtime(true) - $startedAt) * 1000));
 
         try {
-            app(SystemAuditService::class)->record(
+            app(AuditRecorderInterface::class)->record(
                 'cli.command',
                 $exitCode === 0 ? 'success' : 'failed',
                 [
diff --git a/lib/Service/Audit/ApiAuditServiceInterface.php b/lib/Service/Audit/ApiAuditServiceInterface.php
new file mode 100644
index 0000000..aac08ce
--- /dev/null
+++ b/lib/Service/Audit/ApiAuditServiceInterface.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace MintyPHP\Service\Audit;
+
+/**
+ * Core-side contract for API request audit tracking.
+ *
+ * Implemented by the audit module's ApiAuditService when the module is active.
+ * Falls back to NullApiAuditService (no-op) when the audit module is disabled.
+ */
+interface ApiAuditServiceInterface
+{
+    public function startRequestContext(): void;
+
+    public function finish(int $statusCode, ?string $errorCode = null): void;
+
+    public function currentRequestId(): ?string;
+}
diff --git a/lib/Service/Audit/ApiSystemAuditReporterInterface.php b/lib/Service/Audit/ApiSystemAuditReporterInterface.php
new file mode 100644
index 0000000..6f943a6
--- /dev/null
+++ b/lib/Service/Audit/ApiSystemAuditReporterInterface.php
@@ -0,0 +1,16 @@
+<?php
+
+namespace MintyPHP\Service\Audit;
+
+/**
+ * Core-side contract for API system-level audit reporting.
+ *
+ * Implemented by the audit module's ApiSystemAuditReporter when the module is active.
+ * Falls back to NullApiSystemAuditReporter (no-op) when the audit module is disabled.
+ */
+interface ApiSystemAuditReporterInterface
+{
+    public function start(): void;
+
+    public function finish(int $statusCode, ?string $errorCode = null): void;
+}
diff --git a/lib/Service/Audit/NullApiAuditService.php b/lib/Service/Audit/NullApiAuditService.php
new file mode 100644
index 0000000..c4b272c
--- /dev/null
+++ b/lib/Service/Audit/NullApiAuditService.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace MintyPHP\Service\Audit;
+
+/**
+ * No-op API audit service used when the audit module is disabled.
+ */
+final class NullApiAuditService implements ApiAuditServiceInterface
+{
+    public function startRequestContext(): void
+    {
+    }
+
+    public function finish(int $statusCode, ?string $errorCode = null): void
+    {
+    }
+
+    public function currentRequestId(): ?string
+    {
+        return null;
+    }
+}
diff --git a/lib/Service/Audit/NullApiSystemAuditReporter.php b/lib/Service/Audit/NullApiSystemAuditReporter.php
new file mode 100644
index 0000000..8516aee
--- /dev/null
+++ b/lib/Service/Audit/NullApiSystemAuditReporter.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace MintyPHP\Service\Audit;
+
+/**
+ * No-op API system audit reporter used when the audit module is disabled.
+ */
+final class NullApiSystemAuditReporter implements ApiSystemAuditReporterInterface
+{
+    public function start(): void
+    {
+    }
+
+    public function finish(int $statusCode, ?string $errorCode = null): void
+    {
+    }
+}
diff --git a/lib/Support/helpers/app.php b/lib/Support/helpers/app.php
index fe9cb44..017d94a 100644
--- a/lib/Support/helpers/app.php
+++ b/lib/Support/helpers/app.php
@@ -41,24 +41,16 @@ function setAppContainer(\MintyPHP\App\AppContainer $container): void
     );
 
     \MintyPHP\Http\ApiBootstrap::configure(
-        $container->has(\MintyPHP\Module\Audit\Service\ApiAuditService::class)
-            ? static fn () => $container->get(\MintyPHP\Module\Audit\Service\ApiAuditService::class)
-            : null,
+        static fn (): \MintyPHP\Service\Audit\ApiAuditServiceInterface => $container->get(\MintyPHP\Service\Audit\ApiAuditServiceInterface::class),
         static fn (): \MintyPHP\Service\Settings\SettingsApiPolicyGateway => $container->get(\MintyPHP\Service\Settings\SettingsApiPolicyGateway::class),
         static fn (): \MintyPHP\Service\Security\RateLimiterService => $container->get(\MintyPHP\Service\Security\RateLimiterService::class),
-        $container->has(\MintyPHP\Module\Audit\Http\ApiSystemAuditReporter::class)
-            ? static fn () => $container->get(\MintyPHP\Module\Audit\Http\ApiSystemAuditReporter::class)
-            : null
+        static fn (): \MintyPHP\Service\Audit\ApiSystemAuditReporterInterface => $container->get(\MintyPHP\Service\Audit\ApiSystemAuditReporterInterface::class)
     );
 
     \MintyPHP\Http\ApiResponse::configure(
-        $container->has(\MintyPHP\Module\Audit\Service\ApiAuditService::class)
-            ? static fn () => $container->get(\MintyPHP\Module\Audit\Service\ApiAuditService::class)
-            : null,
+        static fn (): \MintyPHP\Service\Audit\ApiAuditServiceInterface => $container->get(\MintyPHP\Service\Audit\ApiAuditServiceInterface::class),
         static fn (): \MintyPHP\Service\Access\AuthorizationService => $container->get(\MintyPHP\Service\Access\AuthorizationService::class),
-        $container->has(\MintyPHP\Module\Audit\Http\ApiSystemAuditReporter::class)
-            ? static fn () => $container->get(\MintyPHP\Module\Audit\Http\ApiSystemAuditReporter::class)
-            : null
+        static fn (): \MintyPHP\Service\Audit\ApiSystemAuditReporterInterface => $container->get(\MintyPHP\Service\Audit\ApiSystemAuditReporterInterface::class)
     );
 
     \MintyPHP\Support\Guard::configure(
diff --git a/modules/audit/lib/Module/Audit/AuditContainerRegistrar.php b/modules/audit/lib/Module/Audit/AuditContainerRegistrar.php
index 465c4a4..a55b904 100644
--- a/modules/audit/lib/Module/Audit/AuditContainerRegistrar.php
+++ b/modules/audit/lib/Module/Audit/AuditContainerRegistrar.php
@@ -11,6 +11,8 @@ use MintyPHP\Module\Audit\Handler\ImportAuditPurgeJobHandler;
 use MintyPHP\Module\Audit\Handler\SystemAuditPurgeJobHandler;
 use MintyPHP\Module\Audit\Handler\UserLifecycleAuditPurgeJobHandler;
 use MintyPHP\Module\Audit\Http\ApiSystemAuditReporter;
+use MintyPHP\Service\Audit\ApiAuditServiceInterface;
+use MintyPHP\Service\Audit\ApiSystemAuditReporterInterface;
 use MintyPHP\Module\Audit\Providers\AuditLayoutProvider;
 use MintyPHP\Module\Audit\Repository\ApiAuditLogRepository;
 use MintyPHP\Module\Audit\Repository\ImportAuditRunRepository;
@@ -68,6 +70,8 @@ final class AuditContainerRegistrar implements ContainerRegistrar
         $container->set(AuditRecorderInterface::class, static fn (AppContainer $c): AuditRecorderInterface => $c->get(SystemAuditService::class));
         $container->set(UserLifecycleAuditInterface::class, static fn (AppContainer $c): UserLifecycleAuditInterface => $c->get(UserLifecycleAuditService::class));
         $container->set(ImportAuditInterface::class, static fn (AppContainer $c): ImportAuditInterface => $c->get(ImportAuditService::class));
+        $container->set(ApiAuditServiceInterface::class, static fn (AppContainer $c): ApiAuditServiceInterface => $c->get(ApiAuditService::class));
+        $container->set(ApiSystemAuditReporterInterface::class, static fn (AppContainer $c): ApiSystemAuditReporterInterface => $c->get(ApiSystemAuditReporter::class));
 
         // Frontend telemetry
         $container->set(FrontendTelemetryIngestService::class, static fn (AppContainer $c): FrontendTelemetryIngestService => new FrontendTelemetryIngestService(
diff --git a/modules/audit/lib/Module/Audit/Http/ApiSystemAuditReporter.php b/modules/audit/lib/Module/Audit/Http/ApiSystemAuditReporter.php
index 5f8729d..ebdf8d1 100644
--- a/modules/audit/lib/Module/Audit/Http/ApiSystemAuditReporter.php
+++ b/modules/audit/lib/Module/Audit/Http/ApiSystemAuditReporter.php
@@ -6,8 +6,9 @@ use MintyPHP\Http\ApiAuth;
 use MintyPHP\Http\RequestContext;
 use MintyPHP\Module\Audit\Domain\SystemAuditOutcome;
 use MintyPHP\Module\Audit\Service\SystemAuditService;
+use MintyPHP\Service\Audit\ApiSystemAuditReporterInterface;
 
-class ApiSystemAuditReporter
+class ApiSystemAuditReporter implements ApiSystemAuditReporterInterface
 {
     /**
      * @var array{
diff --git a/modules/audit/lib/Module/Audit/Service/ApiAuditService.php b/modules/audit/lib/Module/Audit/Service/ApiAuditService.php
index 0d49ac3..651c768 100644
--- a/modules/audit/lib/Module/Audit/Service/ApiAuditService.php
+++ b/modules/audit/lib/Module/Audit/Service/ApiAuditService.php
@@ -6,8 +6,9 @@ use MintyPHP\Http\ApiAuth;
 use MintyPHP\Http\RequestContext;
 use MintyPHP\Http\RequestRuntimeInterface;
 use MintyPHP\Module\Audit\Repository\ApiAuditLogRepository;
+use MintyPHP\Service\Audit\ApiAuditServiceInterface;
 
-class ApiAuditService
+class ApiAuditService implements ApiAuditServiceInterface
 {
     private const RETENTION_DAYS = 90;
     private const MAX_QUERY_KEYS = 30;
diff --git a/tests/Architecture/AuditModuleIsolationContractTest.php b/tests/Architecture/AuditModuleIsolationContractTest.php
index ee425e7..1611299 100644
--- a/tests/Architecture/AuditModuleIsolationContractTest.php
+++ b/tests/Architecture/AuditModuleIsolationContractTest.php
@@ -17,9 +17,13 @@ final class AuditModuleIsolationContractTest extends TestCase
         ));
 
         $allowed = [
+            'ApiAuditServiceInterface.php',
+            'ApiSystemAuditReporterInterface.php',
             'AuditMetadataEnricherInterface.php',
             'AuditRecorderInterface.php',
             'ImportAuditInterface.php',
+            'NullApiAuditService.php',
+            'NullApiSystemAuditReporter.php',
             'NullAuditMetadataEnricher.php',
             'NullAuditRecorder.php',
             'NullImportAudit.php',