diff --git a/src/web/api/audit.test.ts b/src/web/api/audit.test.ts
index b65a658..fec16f3 100644
--- a/src/web/api/audit.test.ts
+++ b/src/web/api/audit.test.ts
@@ -7,6 +7,7 @@ import { createUserStore } from "../../data/users.js";
 import { createSessionStore } from "../../data/sessions.js";
 import { createAuditStore } from "../../data/audit.js";
 import { createPermissionStore } from "../../data/permissions.js";
+import { getDefaultConfig } from "../../data/config.js";
 import { createRequireAuth } from "../middleware/requireAuth.js";
 import { createAuditRouter } from "./audit.js";
 import { SESSION_COOKIE_NAME } from "../auth/validateSession.js";
@@ -34,7 +35,7 @@ describe("audit router", () => {
     app = express();
     app.use(express.json());
     app.use(cookieParser());
-    app.use("/api", createRequireAuth(sessions, permissions));
+    app.use("/api", createRequireAuth(sessions, permissions, () => getDefaultConfig().guestMode));
     app.use("/api/audit", createAuditRouter(audit));
   });
 
diff --git a/src/web/api/bot.test.ts b/src/web/api/bot.test.ts
index 3e0832f..5172567 100644
--- a/src/web/api/bot.test.ts
+++ b/src/web/api/bot.test.ts
@@ -60,7 +60,7 @@ describe("bot router /settings", () => {
     app = express();
     app.use(express.json());
     app.use(cookieParser());
-    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db)));
+    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
     app.use(
       "/api/bot",
       createBotRouter(fakeManager, config, configPath, pino({ level: "silent" }), botDb, avatarStore),
diff --git a/src/web/api/users.test.ts b/src/web/api/users.test.ts
index 35e7c43..c422907 100644
--- a/src/web/api/users.test.ts
+++ b/src/web/api/users.test.ts
@@ -8,6 +8,7 @@ import { createUserStore, type UserStore } from "../../data/users.js";
 import { createSessionStore, type SessionStore } from "../../data/sessions.js";
 import { createAuditStore, type AuditStore } from "../../data/audit.js";
 import { createPermissionStore, type PermissionStore } from "../../data/permissions.js";
+import { getDefaultConfig } from "../../data/config.js";
 import { createRequireAuth } from "../middleware/requireAuth.js";
 import { createUsersRouter } from "./users.js";
 import { SESSION_COOKIE_NAME } from "../auth/validateSession.js";
@@ -17,7 +18,7 @@ function makeApp(botDb: BotDatabase, users: UserStore, sessions: SessionStore) {
   app.use(express.json());
   app.use(cookieParser());
   const permissions = createPermissionStore(botDb.db);
-  const requireAuth = createRequireAuth(sessions, permissions);
+  const requireAuth = createRequireAuth(sessions, permissions, () => getDefaultConfig().guestMode);
   const audit = createAuditStore(botDb.db);
   app.use("/api", requireAuth);
   app.use("/api/users", createUsersRouter(users, sessions, audit, pino({ level: "silent" }), permissions));
@@ -152,7 +153,7 @@ describe("users router", () => {
     const localApp = express();
     localApp.use(express.json());
     localApp.use(cookieParser());
-    localApp.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db)));
+    localApp.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
     localApp.use(
       "/api/users",
       createUsersRouter(users, sessions, brokenAudit, pino({ level: "silent" }), createPermissionStore(botDb.db))
diff --git a/src/web/middleware/requireAdmin.test.ts b/src/web/middleware/requireAdmin.test.ts
index df020d3..f6b25f1 100644
--- a/src/web/middleware/requireAdmin.test.ts
+++ b/src/web/middleware/requireAdmin.test.ts
@@ -6,6 +6,7 @@ import { createDatabase, type BotDatabase } from "../../data/database.js";
 import { createUserStore } from "../../data/users.js";
 import { createSessionStore } from "../../data/sessions.js";
 import { createPermissionStore } from "../../data/permissions.js";
+import { getDefaultConfig } from "../../data/config.js";
 import { createRequireAuth } from "./requireAuth.js";
 import { requireAdmin } from "./requireAdmin.js";
 import { SESSION_COOKIE_NAME } from "../auth/validateSession.js";
@@ -27,7 +28,7 @@ describe("requireAdmin middleware", () => {
     memberCookie = `${SESSION_COOKIE_NAME}=${sessions.createSession(member.id).token}`;
     app = express();
     app.use(cookieParser());
-    app.use(createRequireAuth(sessions, permissions));
+    app.use(createRequireAuth(sessions, permissions, () => getDefaultConfig().guestMode));
     app.use(requireAdmin);
     app.get("/admin-only", (_req, res) => res.json({ ok: true }));
   });
diff --git a/src/web/middleware/requireAuth.test.ts b/src/web/middleware/requireAuth.test.ts
index fe9780f..12d9519 100644
--- a/src/web/middleware/requireAuth.test.ts
+++ b/src/web/middleware/requireAuth.test.ts
@@ -1,4 +1,4 @@
-import { describe, it, expect, beforeEach, afterEach } from "vitest";
+import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
 import express from "express";
 import cookieParser from "cookie-parser";
 import request from "supertest";
@@ -24,7 +24,21 @@ describe("requireAuth middleware", () => {
 
     app = express();
     app.use(cookieParser());
-    app.use(createRequireAuth(sessions, permissions));
+    app.use(
+      createRequireAuth(sessions, permissions, () => ({
+        enabled: true,
+        bots: "all",
+        permissions: {
+          addToQueue: true,
+          playNext: true,
+          playNow: true,
+          skip: true,
+          transport: true,
+          removeClear: true,
+          playMode: true,
+        },
+      }))
+    );
     app.get("/protected", (req, res) => {
       res.json({ ok: true, user: (req as any).user });
     });
@@ -68,4 +82,34 @@ describe("requireAuth middleware", () => {
     expect(refreshed).toBeDefined();
     expect(refreshed!).toMatch(/Max-Age=\d+/);
   });
+
+  // A guest session is rejected (401) when guest mode is disabled.
+  it("rejects a guest session when guest mode is disabled", () => {
+    const sessions: any = { validateAndTouch: () => ({ userId: "__guest__", username: "游客", role: "guest" }) };
+    const permissions: any = { getCapabilities: () => [], getBotAccess: () => [] };
+    const getGuestConfig = () => ({ enabled: false, bots: "all" as const, permissions: {} as any });
+    const mw = createRequireAuth(sessions, permissions, getGuestConfig);
+    const req: any = { headers: { cookie: "tsmb_session=x" } };
+    const res: any = { statusCode: 0, cleared: false, clearCookie() { this.cleared = true; }, status(c: number) { this.statusCode = c; return this; }, json() { return this; }, cookie() {} };
+    const next = vi.fn();
+    mw(req, res, next);
+    expect(res.statusCode).toBe(401);
+    expect(next).not.toHaveBeenCalled();
+  });
+
+  it("attaches guest permissions when guest mode is enabled", () => {
+    const sessions: any = { validateAndTouch: () => ({ userId: "__guest__", username: "游客", role: "guest" }) };
+    const permissions: any = { getCapabilities: () => [], getBotAccess: () => [] };
+    const perms = { addToQueue: true, playNext: false, playNow: false, skip: false, transport: false, removeClear: false, playMode: false };
+    const getGuestConfig = () => ({ enabled: true, bots: ["bot1"], permissions: perms });
+    const mw = createRequireAuth(sessions, permissions, getGuestConfig);
+    const req: any = { headers: { cookie: "tsmb_session=x" }, secure: false };
+    const res: any = { status() { return this; }, json() { return this; }, cookie() {}, clearCookie() {} };
+    const next = vi.fn();
+    mw(req, res, next);
+    expect(next).toHaveBeenCalled();
+    expect(req.user.role).toBe("guest");
+    expect(req.user.guest.addToQueue).toBe(true);
+    expect(req.user.bots instanceof Set && req.user.bots.has("bot1")).toBe(true);
+  });
 });
diff --git a/src/web/middleware/requireAuth.ts b/src/web/middleware/requireAuth.ts
index 6865f21..1dc9b36 100644
--- a/src/web/middleware/requireAuth.ts
+++ b/src/web/middleware/requireAuth.ts
@@ -1,7 +1,8 @@
 import type { Request, Response, NextFunction, RequestHandler } from "express";
 import type { SessionStore } from "../../data/sessions.js";
 import { SESSION_TTL_MS } from "../../data/sessions.js";
-import { resolvePermissionContext, type PermissionStore } from "../../data/permissions.js";
+import { resolvePermissionContext, type PermissionStore, type GuestPermissions } from "../../data/permissions.js";
+import type { GuestModeConfig } from "../../data/config.js";
 import {
   validateSessionFromHeaders,
   extractSessionToken,
@@ -13,14 +14,19 @@ declare module "express-serve-static-core" {
     user?: {
       id: string;
       username: string;
-      role: "admin" | "member";
+      role: "admin" | "member" | "guest";
       capabilities?: Set<string>;
       bots?: "all" | Set<string>;
+      guest?: GuestPermissions;
     };
   }
 }
 
-export function createRequireAuth(sessions: SessionStore, permissions: PermissionStore): RequestHandler {
+export function createRequireAuth(
+  sessions: SessionStore,
+  permissions: PermissionStore,
+  getGuestConfig: () => GuestModeConfig
+): RequestHandler {
   return function requireAuth(req: Request, res: Response, next: NextFunction) {
     const result = validateSessionFromHeaders(req.headers.cookie, sessions);
     if (!result) {
@@ -28,13 +34,27 @@ export function createRequireAuth(sessions: SessionStore, permissions: Permissio
       res.status(401).json({ error: "unauthenticated" });
       return;
     }
-    const ctx = resolvePermissionContext(result.role, result.userId, permissions);
+    // A guest session is only valid while guest mode is enabled. Disabling it
+    // immediately invalidates any in-flight guest sessions.
+    const guestCfg = getGuestConfig();
+    if (result.role === "guest" && !guestCfg.enabled) {
+      res.clearCookie(SESSION_COOKIE_NAME, { path: "/" });
+      res.status(401).json({ error: "unauthenticated" });
+      return;
+    }
+    const ctx = resolvePermissionContext(
+      result.role,
+      result.userId,
+      permissions,
+      result.role === "guest" ? { bots: guestCfg.bots, permissions: guestCfg.permissions } : undefined
+    );
     req.user = {
       id: result.userId,
       username: result.username,
       role: result.role,
       capabilities: ctx.capabilities,
       bots: ctx.bots,
+      guest: ctx.guest,
     };
     const token = extractSessionToken(req.headers.cookie);
     if (token) {
diff --git a/src/web/server.ts b/src/web/server.ts
index e89e5bf..b1d5809 100755
--- a/src/web/server.ts
+++ b/src/web/server.ts
@@ -98,7 +98,7 @@ export function createWebServer(options: WebServerOptions): WebServer {
   app.use("/api/session", createSessionRouter(users, sessions, audit, logger, permissions));
 
   // ─── Gates for everything else under /api ───────────────────────────────
-  const requireAuth = createRequireAuth(sessions, permissions);
+  const requireAuth = createRequireAuth(sessions, permissions, () => options.config.guestMode);
   app.use("/api", csrfOriginCheck);
   app.use("/api", requireAuth);