diff --git a/packages/element-web-module-api/src/api/client.ts b/packages/element-web-module-api/src/api/client.ts
new file mode 100644
index 0000000000..1b9bed97dd
--- /dev/null
+++ b/packages/element-web-module-api/src/api/client.ts
@@ -0,0 +1,45 @@
+/*
+Copyright 2025 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import type { Room } from "../models/Room";
+
+/**
+ * Modify account data stored on the homeserver.
+ * @public
+ */
+export interface AccountDataApi {
+    /**
+     * Fetch account data stored from homeserver.
+     */
+    get(eventType: string): unknown;
+    /**
+     * Sett account data on the homeserver.
+     */
+    set(eventType: string, content: unknown): Promise<void>;
+    /**
+     * Delete account data from homeserver.
+     */
+    delete(eventType: string): Promise<void>;
+}
+
+/**
+ * Access some limited functionality from the SDK.
+ * @public
+ */
+export interface ClientApi {
+    /**
+     * Use this to modify account data on the homeserver.
+     */
+    getAccountDataApi: () => AccountDataApi;
+
+    /**
+     * Fetch room by id from SDK.
+     * @param id - Id of the room to get
+     * @returns Room object from SDK
+     */
+    getRoom: (id: string) => Room | null;
+}
diff --git a/packages/element-web-module-api/src/api/index.ts b/packages/element-web-module-api/src/api/index.ts
index dacc7501be..f95479012c 100644
--- a/packages/element-web-module-api/src/api/index.ts
+++ b/packages/element-web-module-api/src/api/index.ts
@@ -17,6 +17,7 @@ import { AccountAuthApiExtension } from "./auth.ts";
 import { ProfileApiExtension } from "./profile.ts";
 import { ExtrasApi } from "./extras.ts";
 import { BuiltinsApi } from "./builtins.ts";
+import { ClientApi } from "./client.ts";
 
 /**
  * Module interface for modules to implement.
@@ -123,6 +124,11 @@ export interface Api
      */
     readonly extras: ExtrasApi;
 
+    /**
+     * Access some very specific functionality from the client.
+     */
+    readonly client: ClientApi;
+
     /**
      * Create a ReactDOM root for rendering React components.
      * Exposed to allow modules to avoid needing to bundle their own ReactDOM.
diff --git a/packages/element-web-module-api/src/index.ts b/packages/element-web-module-api/src/index.ts
index 4935d10681..64f2002a27 100644
--- a/packages/element-web-module-api/src/index.ts
+++ b/packages/element-web-module-api/src/index.ts
@@ -20,4 +20,5 @@ export type * from "./api/dialog";
 export type * from "./api/profile";
 export type * from "./api/navigation";
 export type * from "./api/builtins";
+export type * from "./api/client";
 export * from "./api/watchable";