diff --git a/apps/api/src/middleware/auth.ts b/apps/api/src/middleware/auth.ts
index a044b5a..35fd5d1 100644
--- a/apps/api/src/middleware/auth.ts
+++ b/apps/api/src/middleware/auth.ts
@@ -1,5 +1,6 @@
 import type { Context, MiddlewareHandler } from 'hono';
 import { createRemoteJWKSet, jwtVerify } from 'jose';
+import { fireFirstUseOnce } from '../services/aura-client.ts';
 
 /**
  * Auth-Middleware der Cards-API (Phase 2 Auth-Föderation).
@@ -81,6 +82,9 @@ export const authMiddleware: MiddlewareHandler<{ Variables: AuthVars }> = async
 			c.set('userId', claims.sub);
 			c.set('tier', claims.tier);
 			c.set('authMode', 'jwt');
+			// Cross-App-Aura-Hook: erste Wordeck-Aktion → 25 Aura einmalig.
+			// Reason-Katalog: mana/docs/playbooks/AURA_PER_APP_HOOKS.md.
+			fireFirstUseOnce(claims.sub);
 			await next();
 			return;
 		}
diff --git a/apps/api/src/services/aura-client.ts b/apps/api/src/services/aura-client.ts
new file mode 100644
index 0000000..fc63e2a
--- /dev/null
+++ b/apps/api/src/services/aura-client.ts
@@ -0,0 +1,38 @@
+/**
+ * Aura-Client für Service-to-Service-Calls an mana-admin.
+ *
+ * Heute: nur `fireFirstUseOnce` für den Cross-App-Hook
+ * `onboarding.first_use` (25 Aura, einmalig).
+ *
+ * Server-seitig (mana-admin Migration 0003) gibt es UNIQUE-Indizes
+ * auf `aura_ledger(user_id, reason)` für einmalig-Reasons, also
+ * sind Doppel-Awards auf DB-Ebene unmöglich. Der Process-Cache
+ * hier ist reine HTTP-Overhead-Reduktion.
+ *
+ * Reason-Katalog: mana/docs/playbooks/AURA_PER_APP_HOOKS.md.
+ */
+
+const firedFirstUse = new Set<string>();
+
+export function fireFirstUseOnce(userId: string): void {
+	if (firedFirstUse.has(userId)) return;
+	firedFirstUse.add(userId);
+
+	const adminUrl = process.env.MANA_ADMIN_URL ?? 'http://localhost:3071';
+	const serviceKey = process.env.MANA_SERVICE_KEY ?? 'dev-service-key';
+
+	fetch(`${adminUrl}/api/v1/internal/aura/award`, {
+		method: 'POST',
+		headers: {
+			'Content-Type': 'application/json',
+			'X-Service-Key': serviceKey,
+		},
+		body: JSON.stringify({
+			userId,
+			delta: 25,
+			reason: 'onboarding.first_use',
+			refId: userId,
+			context: { app: 'wordeck' },
+		}),
+	}).catch(() => {});
+}