diff --git a/api-v3/test/unit/f5-runtime-di-contract.test.ts b/api-v3/test/unit/f5-runtime-di-contract.test.ts
new file mode 100644
index 0000000..cef877e
--- /dev/null
+++ b/api-v3/test/unit/f5-runtime-di-contract.test.ts
@@ -0,0 +1,20 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { MODULE_METADATA } from '@nestjs/common/constants';
+import { AssetMasterModule } from '../../src/asset-master/asset-master.module';
+import { InventoryFunctionService } from '../../src/asset-master/inventory-function.service';
+import { MergedInventoryDossierService } from '../../src/asset-master/merged-inventory-dossier.service';
+
+test('F5 AssetMasterModule keeps dossier-only function dependency injectable', () => {
+  const providers = (Reflect.getMetadata(MODULE_METADATA.PROVIDERS, AssetMasterModule) ?? []) as unknown[];
+  const dossierDependencies = (Reflect.getMetadata('design:paramtypes', MergedInventoryDossierService) ?? []) as unknown[];
+
+  assert.ok(
+    dossierDependencies.includes(InventoryFunctionService),
+    'MergedInventoryDossierService must still declare InventoryFunctionService for historical dossier data',
+  );
+  assert.ok(
+    providers.includes(InventoryFunctionService),
+    'AssetMasterModule must provide InventoryFunctionService so production Nest bootstrap can resolve the dossier',
+  );
+});