diff --git a/src/index.ts b/src/index.ts
index 6b7d79502..ffb273180 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -16,51 +16,24 @@ import { startHostSweep, stopHostSweep } from './host-sweep.js';
 import { routeInbound } from './router.js';
 import { log } from './log.js';
 
-/**
- * Response handler registry.
- *
- * Button-click / question responses arrive via the channel adapter's
- * `onAction` callback. Core iterates registered handlers in registration
- * order; the first one that returns `true` claims the response. Unclaimed
- * responses are logged and dropped.
- *
- * Current consumers: interactive module (pending_questions), approvals
- * module (pending_approvals + OneCLI). If neither is loaded, every click
- * logs "Unclaimed response".
- */
-export interface ResponsePayload {
-  questionId: string;
-  value: string;
-  userId: string | null;
-  channelType: string;
-  platformId: string;
-  threadId: string | null;
-}
-
-export type ResponseHandler = (payload: ResponsePayload) => Promise<boolean>;
-
-const responseHandlers: ResponseHandler[] = [];
-
-export function registerResponseHandler(handler: ResponseHandler): void {
-  responseHandlers.push(handler);
-}
-
-/**
- * Shutdown callbacks. Modules with teardown needs (timers, outbound sockets)
- * register here. Called in registration order during SIGTERM / SIGINT
- * before core's delivery/sweep/channel teardown.
- *
- * Not a general-purpose registry — narrow lifecycle hook only.
- */
-type ShutdownCallback = () => void | Promise<void>;
-const shutdownCallbacks: ShutdownCallback[] = [];
-
-export function onShutdown(cb: ShutdownCallback): void {
-  shutdownCallbacks.push(cb);
-}
+// Response + shutdown registries live in response-registry.ts to break the
+// circular import cycle: src/index.ts imports src/modules/index.js for side
+// effects, and the modules call registerResponseHandler/onShutdown at top
+// level — which would hit a TDZ error if the arrays lived here. Re-exported
+// here so existing callers see the same surface.
+import {
+  registerResponseHandler,
+  getResponseHandlers,
+  onShutdown,
+  getShutdownCallbacks,
+  type ResponsePayload,
+  type ResponseHandler,
+} from './response-registry.js';
+export { registerResponseHandler, onShutdown };
+export type { ResponsePayload, ResponseHandler };
 
 async function dispatchResponse(payload: ResponsePayload): Promise<void> {
-  for (const handler of responseHandlers) {
+  for (const handler of getResponseHandlers()) {
     try {
       const claimed = await handler(payload);
       if (claimed) return;
@@ -202,7 +175,7 @@ function buildConversationConfigs(channelType: string): ConversationConfig[] {
 /** Graceful shutdown. */
 async function shutdown(signal: string): Promise<void> {
   log.info('Shutdown signal received', { signal });
-  for (const cb of shutdownCallbacks) {
+  for (const cb of getShutdownCallbacks()) {
     try {
       await cb();
     } catch (err) {
diff --git a/src/modules/approvals/index.ts b/src/modules/approvals/index.ts
index 3f3000860..e159deb79 100644
--- a/src/modules/approvals/index.ts
+++ b/src/modules/approvals/index.ts
@@ -11,7 +11,7 @@
  *   - A shutdown callback that stops the OneCLI handler cleanly.
  */
 import { registerDeliveryAction, onDeliveryAdapterReady } from '../../delivery.js';
-import { registerResponseHandler, onShutdown } from '../../index.js';
+import { registerResponseHandler, onShutdown } from '../../response-registry.js';
 import { handleAddMcpServer, handleInstallPackages, handleRequestRebuild } from './request-approval.js';
 import { handleApprovalsResponse } from './response-handler.js';
 import { startOneCLIApprovalHandler, stopOneCLIApprovalHandler } from './onecli-approvals.js';
diff --git a/src/modules/approvals/response-handler.ts b/src/modules/approvals/response-handler.ts
index 1f4bc6802..803268a38 100644
--- a/src/modules/approvals/response-handler.ts
+++ b/src/modules/approvals/response-handler.ts
@@ -16,7 +16,7 @@ import { updateContainerConfig } from '../../container-config.js';
 import { buildAgentGroupImage, killContainer, wakeContainer } from '../../container-runner.js';
 import { getAgentGroup } from '../../db/agent-groups.js';
 import { deletePendingApproval, getPendingApproval, getSession } from '../../db/sessions.js';
-import type { ResponsePayload } from '../../index.js';
+import type { ResponsePayload } from '../../response-registry.js';
 import { log } from '../../log.js';
 import { writeSessionMessage } from '../../session-manager.js';
 import type { PendingApproval } from '../../types.js';
diff --git a/src/modules/interactive/index.ts b/src/modules/interactive/index.ts
index f24794b4c..5a3b8afc1 100644
--- a/src/modules/interactive/index.ts
+++ b/src/modules/interactive/index.ts
@@ -13,7 +13,7 @@
 import { getDb, hasTable } from '../../db/connection.js';
 import { deletePendingQuestion, getPendingQuestion, getSession } from '../../db/sessions.js';
 import { wakeContainer } from '../../container-runner.js';
-import { registerResponseHandler, type ResponsePayload } from '../../index.js';
+import { registerResponseHandler, type ResponsePayload } from '../../response-registry.js';
 import { log } from '../../log.js';
 import { writeSessionMessage } from '../../session-manager.js';
 
diff --git a/src/response-registry.ts b/src/response-registry.ts
new file mode 100644
index 000000000..60e04c998
--- /dev/null
+++ b/src/response-registry.ts
@@ -0,0 +1,45 @@
+/**
+ * Response handler + shutdown callback registries.
+ *
+ * Extracted from index.ts so that modules calling `registerResponseHandler()`
+ * or `onShutdown()` at import time don't hit a TDZ error on the const-array
+ * declarations. index.ts imports src/modules/index.js for its side effects,
+ * which triggers module registrations that would otherwise happen before
+ * index.ts's own const initializers have run.
+ *
+ * Keep this file dependency-free (log.js is fine, but nothing from
+ * modules/* or index.ts itself). Any file imported here must not in turn
+ * import from src/index.ts, or the cycle returns.
+ */
+
+export interface ResponsePayload {
+  questionId: string;
+  value: string;
+  userId: string | null;
+  channelType: string;
+  platformId: string;
+  threadId: string | null;
+}
+
+export type ResponseHandler = (payload: ResponsePayload) => Promise<boolean>;
+
+const responseHandlers: ResponseHandler[] = [];
+
+export function registerResponseHandler(handler: ResponseHandler): void {
+  responseHandlers.push(handler);
+}
+
+export function getResponseHandlers(): readonly ResponseHandler[] {
+  return responseHandlers;
+}
+
+type ShutdownCallback = () => void | Promise<void>;
+const shutdownCallbacks: ShutdownCallback[] = [];
+
+export function onShutdown(cb: ShutdownCallback): void {
+  shutdownCallbacks.push(cb);
+}
+
+export function getShutdownCallbacks(): readonly ShutdownCallback[] {
+  return shutdownCallbacks;
+}