diff --git a/packages/adapters/hono/src/hono.test.ts b/packages/adapters/hono/src/hono.test.ts
index 48ac35124..1a0f52b4d 100644
--- a/packages/adapters/hono/src/hono.test.ts
+++ b/packages/adapters/hono/src/hono.test.ts
@@ -94,6 +94,77 @@ describe('createHonoApp', () => {
     });
   });
 
+  describe('Auth via AuthPlugin service', () => {
+    it('uses kernel.getService("auth") when available', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ user: { id: '1' } }), {
+          status: 200,
+          headers: { 'Content-Type': 'application/json' },
+        }),
+      );
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const app = createHonoApp({ kernel: kernelWithAuth });
+      const res = await app.request('/api/auth/sign-in/email', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ email: 'a@b.com', password: 'pass' }),
+      });
+      expect(res.status).toBe(200);
+      const json = await res.json();
+      expect(json.user.id).toBe('1');
+      expect(kernelWithAuth.getService).toHaveBeenCalledWith('auth');
+      expect(mockHandleRequest).toHaveBeenCalledWith(expect.any(Request));
+      expect(mockDispatcher.handleAuth).not.toHaveBeenCalled();
+    });
+
+    it('falls back to dispatcher.handleAuth when auth service is not available', async () => {
+      const kernelWithoutAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue(null),
+      };
+      const app = createHonoApp({ kernel: kernelWithoutAuth });
+      const res = await app.request('/api/auth/login', { method: 'POST' });
+      expect(res.status).toBe(200);
+      expect(mockDispatcher.handleAuth).toHaveBeenCalled();
+    });
+
+    it('forwards GET requests to auth service', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ session: { token: 'abc' } }), {
+          status: 200,
+          headers: { 'Content-Type': 'application/json' },
+        }),
+      );
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const app = createHonoApp({ kernel: kernelWithAuth });
+      const res = await app.request('/api/auth/get-session', { method: 'GET' });
+      expect(res.status).toBe(200);
+      const json = await res.json();
+      expect(json.session.token).toBe('abc');
+      expect(mockHandleRequest).toHaveBeenCalled();
+    });
+
+    it('returns error when auth service throws', async () => {
+      const mockHandleRequest = vi.fn().mockRejectedValue(new Error('Auth failed'));
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const app = createHonoApp({ kernel: kernelWithAuth });
+      const res = await app.request('/api/auth/sign-in/email', { method: 'POST' });
+      expect(res.status).toBe(500);
+      const json = await res.json();
+      expect(json.success).toBe(false);
+      expect(json.error.message).toBe('Auth failed');
+    });
+  });
+
   describe('GraphQL Endpoint', () => {
     it('POST /api/graphql calls handleGraphQL', async () => {
       const app = createHonoApp({ kernel: mockKernel });
diff --git a/packages/adapters/hono/src/index.ts b/packages/adapters/hono/src/index.ts
index 813d87b9f..58178e676 100644
--- a/packages/adapters/hono/src/index.ts
+++ b/packages/adapters/hono/src/index.ts
@@ -66,7 +66,17 @@ export function createHonoApp(options: ObjectStackHonoOptions) {
   // --- 1. Auth ---
   app.all(`${prefix}/auth/*`, async (c) => {
     try {
-      // subpath from /api/auth/login -> login
+      // Try AuthPlugin service first (preferred path)
+      const authService = typeof options.kernel.getService === 'function'
+        ? options.kernel.getService('auth')
+        : null;
+
+      if (authService && typeof authService.handleRequest === 'function') {
+        const response = await authService.handleRequest(c.req.raw);
+        return response;
+      }
+
+      // Fallback to legacy dispatcher
       const path = c.req.path.substring(c.req.path.indexOf('/auth/') + 6);
       const body = await c.req.parseBody().catch(() => ({})); 
       
diff --git a/packages/adapters/nestjs/src/index.ts b/packages/adapters/nestjs/src/index.ts
index 2ca295f96..de741e6a9 100644
--- a/packages/adapters/nestjs/src/index.ts
+++ b/packages/adapters/nestjs/src/index.ts
@@ -106,6 +106,42 @@ export class ObjectStackController {
   @All('auth/*')
   async auth(@Req() req: any, @Res() res: any, @Body() body: any) {
     try {
+        // Try AuthPlugin service first (preferred path)
+        const kernel = this.service.getKernel();
+        const authService = typeof kernel.getService === 'function'
+          ? kernel.getService('auth')
+          : null;
+
+        if (authService && typeof authService.handleRequest === 'function') {
+          // Construct a Web standard Request from the Express/Fastify request
+          const protocol = req.protocol || 'http';
+          const host = req.get?.('host') || req.headers?.host || 'localhost';
+          const url = `${protocol}://${host}${req.originalUrl || req.url}`;
+          const headers = new Headers();
+          if (req.headers) {
+            Object.entries(req.headers).forEach(([k, v]) => {
+              if (typeof v === 'string') headers.set(k, v);
+              else if (Array.isArray(v)) headers.set(k, v.join(', '));
+            });
+          }
+          const init: RequestInit = { method: req.method, headers };
+          if (req.method !== 'GET' && req.method !== 'HEAD' && body) {
+            init.body = JSON.stringify(body);
+            if (!headers.has('content-type')) {
+              headers.set('content-type', 'application/json');
+            }
+          }
+          const webRequest = new Request(url, init);
+          const response = await authService.handleRequest(webRequest);
+
+          // Convert Web Response to Express/Fastify response
+          res.status(response.status);
+          response.headers.forEach((v: string, k: string) => res.setHeader(k, v));
+          const text = await response.text();
+          return res.send(text);
+        }
+
+        // Fallback to legacy dispatcher
         const path = req.params[0] || req.url.split('/auth/')[1]?.split('?')[0] || '';
         const result = await this.service.dispatcher.handleAuth(path, req.method, body, { request: req, response: res });
         return this.normalizeResponse(result, res);
diff --git a/packages/adapters/nestjs/src/nestjs.test.ts b/packages/adapters/nestjs/src/nestjs.test.ts
index 63ca6c9ec..a83a3dec9 100644
--- a/packages/adapters/nestjs/src/nestjs.test.ts
+++ b/packages/adapters/nestjs/src/nestjs.test.ts
@@ -190,6 +190,109 @@ describe('ObjectStackController', () => {
     });
   });
 
+  describe('auth() via AuthPlugin service', () => {
+    it('uses kernel.getService("auth") when available', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ user: { id: '1' } }), {
+          status: 200,
+          headers: new Headers({ 'Content-Type': 'application/json' }),
+        }),
+      );
+      const kernelWithAuth = {
+        ...createMockKernel(),
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const svc = new ObjectStackService(kernelWithAuth);
+      const ctrl = new ObjectStackController(svc);
+      const r = createMockRes();
+      const req = {
+        params: { 0: 'sign-in/email' },
+        url: '/api/auth/sign-in/email',
+        method: 'POST',
+        protocol: 'http',
+        get: (key: string) => key === 'host' ? 'localhost' : undefined,
+        headers: { 'content-type': 'application/json' },
+        originalUrl: '/api/auth/sign-in/email',
+      };
+
+      await ctrl.auth(req, r, { email: 'a@b.com', password: 'pass' });
+
+      expect(kernelWithAuth.getService).toHaveBeenCalledWith('auth');
+      expect(mockHandleRequest).toHaveBeenCalledWith(expect.any(Request));
+      expect(r._status).toBe(200);
+    });
+
+    it('falls back to dispatcher when auth service is not available', async () => {
+      const kernelWithoutAuth = {
+        ...createMockKernel(),
+        getService: vi.fn().mockReturnValue(null),
+      };
+      const svc = new ObjectStackService(kernelWithoutAuth);
+      const ctrl = new ObjectStackController(svc);
+      const r = createMockRes();
+      const req = { params: { 0: 'login' }, url: '/api/auth/login', method: 'POST' };
+
+      await ctrl.auth(req, r, { email: 'a@b.com' });
+
+      expect(svc.dispatcher.handleAuth).toHaveBeenCalled();
+    });
+
+    it('forwards GET requests to auth service', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ session: { token: 'abc' } }), {
+          status: 200,
+          headers: new Headers({ 'Content-Type': 'application/json' }),
+        }),
+      );
+      const kernelWithAuth = {
+        ...createMockKernel(),
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const svc = new ObjectStackService(kernelWithAuth);
+      const ctrl = new ObjectStackController(svc);
+      const r = createMockRes();
+      const req = {
+        params: { 0: 'get-session' },
+        url: '/api/auth/get-session',
+        method: 'GET',
+        protocol: 'http',
+        get: (key: string) => key === 'host' ? 'localhost' : undefined,
+        headers: {},
+        originalUrl: '/api/auth/get-session',
+      };
+
+      await ctrl.auth(req, r, {});
+
+      expect(mockHandleRequest).toHaveBeenCalled();
+      expect(r._status).toBe(200);
+    });
+
+    it('returns error when auth service throws', async () => {
+      const mockHandleRequest = vi.fn().mockRejectedValue(new Error('Auth failed'));
+      const kernelWithAuth = {
+        ...createMockKernel(),
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const svc = new ObjectStackService(kernelWithAuth);
+      const ctrl = new ObjectStackController(svc);
+      const r = createMockRes();
+      const req = {
+        params: { 0: 'sign-in/email' },
+        url: '/api/auth/sign-in/email',
+        method: 'POST',
+        protocol: 'http',
+        get: (key: string) => key === 'host' ? 'localhost' : undefined,
+        headers: {},
+        originalUrl: '/api/auth/sign-in/email',
+      };
+
+      await ctrl.auth(req, r, {});
+
+      expect(r._status).toBe(500);
+      expect(r._body.success).toBe(false);
+    });
+  });
+
   describe('metadata()', () => {
     it('dispatches to handleMetadata with extracted path', async () => {
       const req = { params: { 0: '' }, url: '/api/meta/objects', method: 'GET' };
diff --git a/packages/adapters/nextjs/src/index.ts b/packages/adapters/nextjs/src/index.ts
index f11aa74c0..efb5e47c6 100644
--- a/packages/adapters/nextjs/src/index.ts
+++ b/packages/adapters/nextjs/src/index.ts
@@ -61,6 +61,21 @@ export function createRouteHandler(options: NextAdapterOptions) {
 
         // --- 1. Auth ---
         if (segments[0] === 'auth') {
+           // Try AuthPlugin service first (preferred path)
+           const authService = typeof options.kernel.getService === 'function'
+             ? options.kernel.getService('auth')
+             : null;
+
+           if (authService && typeof authService.handleRequest === 'function') {
+             const response = await authService.handleRequest(req);
+             // Convert Web Response to NextResponse
+             const body = await response.text();
+             const headers: Record<string, string> = {};
+             response.headers.forEach((v: string, k: string) => { headers[k] = v; });
+             return new NextResponse(body, { status: response.status, headers });
+           }
+
+           // Fallback to legacy dispatcher
            const subPath = segments.slice(1).join('/');
            const body = method === 'POST' ? await req.json().catch(() => ({})) : {};
            const result = await dispatcher.handleAuth(subPath, method, body, { request: req });
diff --git a/packages/adapters/nextjs/src/nextjs.test.ts b/packages/adapters/nextjs/src/nextjs.test.ts
index b1c300993..d1ce2a3ef 100644
--- a/packages/adapters/nextjs/src/nextjs.test.ts
+++ b/packages/adapters/nextjs/src/nextjs.test.ts
@@ -150,6 +150,71 @@ describe('createRouteHandler', () => {
     });
   });
 
+  describe('Auth via AuthPlugin service', () => {
+    it('uses kernel.getService("auth") when available', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ user: { id: '1' } }), {
+          status: 200,
+          headers: { 'Content-Type': 'application/json' },
+        }),
+      );
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const handler = createRouteHandler({ kernel: kernelWithAuth });
+      const req = makeReq('http://localhost/api/auth/sign-in/email', 'POST', { email: 'a@b.com', password: 'pass' });
+      const res = await handler(req, { params: { objectstack: ['auth', 'sign-in', 'email'] } });
+      expect(res.status).toBe(200);
+      expect(kernelWithAuth.getService).toHaveBeenCalledWith('auth');
+      expect(mockHandleRequest).toHaveBeenCalled();
+      expect(mockDispatcher.handleAuth).not.toHaveBeenCalled();
+    });
+
+    it('falls back to dispatcher.handleAuth when auth service is not available', async () => {
+      const kernelWithoutAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue(null),
+      };
+      const handler = createRouteHandler({ kernel: kernelWithoutAuth });
+      const req = makeReq('http://localhost/api/auth/login', 'POST', { email: 'a@b.com' });
+      const res = await handler(req, { params: { objectstack: ['auth', 'login'] } });
+      expect(res.status).toBe(200);
+      expect(mockDispatcher.handleAuth).toHaveBeenCalled();
+    });
+
+    it('forwards GET requests to auth service', async () => {
+      const mockHandleRequest = vi.fn().mockResolvedValue(
+        new Response(JSON.stringify({ session: { token: 'abc' } }), {
+          status: 200,
+          headers: { 'Content-Type': 'application/json' },
+        }),
+      );
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const handler = createRouteHandler({ kernel: kernelWithAuth });
+      const req = makeReq('http://localhost/api/auth/get-session', 'GET');
+      const res = await handler(req, { params: { objectstack: ['auth', 'get-session'] } });
+      expect(res.status).toBe(200);
+      expect(mockHandleRequest).toHaveBeenCalled();
+    });
+
+    it('returns error when auth service throws', async () => {
+      const mockHandleRequest = vi.fn().mockRejectedValue(new Error('Auth failed'));
+      const kernelWithAuth = {
+        ...mockKernel,
+        getService: vi.fn().mockReturnValue({ handleRequest: mockHandleRequest }),
+      };
+      const handler = createRouteHandler({ kernel: kernelWithAuth });
+      const req = makeReq('http://localhost/api/auth/sign-in/email', 'POST', { email: 'a@b.com' });
+      const res = await handler(req, { params: { objectstack: ['auth', 'sign-in', 'email'] } });
+      expect(res.status).toBe(500);
+      expect(res.body.success).toBe(false);
+    });
+  });
+
   describe('GraphQL Endpoint', () => {
     it('POST graphql calls handleGraphQL', async () => {
       const handler = createRouteHandler({ kernel: mockKernel });