diff --git a/sdk/main.ts b/sdk/main.ts
index 4a7926a16..6347d1421 100644
--- a/sdk/main.ts
+++ b/sdk/main.ts
@@ -46,7 +46,10 @@ import {
 // Can this be done in the tsconfig.json
 import { type TextStreamInfo } from "../node_modules/livekit-client/dist/src/room/types";
 import { type Behavior, constant } from "../src/state/Behavior";
-import { createCallViewModel$ } from "../src/state/CallViewModel/CallViewModel";
+import {
+  callViewModelOptionsFromParams,
+  createCallViewModel$,
+} from "../src/state/CallViewModel/CallViewModel";
 import { ObservableScope } from "../src/state/ObservableScope";
 import { getUrlParams } from "../src/UrlParams";
 import { MuteStates } from "../src/state/MuteStates";
@@ -113,7 +116,8 @@ export async function createMatrixRTCSdk(
   logger.info("client created");
 
   // url params
-  const { roomId, controlledAudioDevices, callIntent } = getUrlParams();
+  const urlParams = getUrlParams();
+  const { roomId, controlledAudioDevices, callIntent } = urlParams;
   if (roomId === null) throw Error("could not get roomId from url params");
   const room = client.getRoom(roomId);
   if (room === null) throw Error("could not get room from client");
@@ -144,10 +148,9 @@ export async function createMatrixRTCSdk(
     mediaDevices,
     muteStates,
     {
+      ...callViewModelOptionsFromParams(urlParams),
       encryptionSystem: { kind: E2eeType.PER_PARTICIPANT },
       hostBridge,
-      controlledAudioDevices,
-      callIntent,
     },
     of({}),
     of({}),
diff --git a/src/room/InCallView.tsx b/src/room/InCallView.tsx
index ef1e1f988..97fb75438 100644
--- a/src/room/InCallView.tsx
+++ b/src/room/InCallView.tsx
@@ -41,6 +41,7 @@ import { type MatrixInfo } from "./VideoPreview";
 import { InviteButton } from "../button/InviteButton";
 import {
   type CallViewModel,
+  callViewModelOptionsFromParams,
   createCallViewModel$,
 } from "../state/CallViewModel/CallViewModel.ts";
 import { Grid, type TileProps } from "../grid/Grid";
@@ -123,16 +124,8 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
     rootLogger.info("START CALL VIEW SCOPE");
     const scope = new ObservableScope();
     const reactionsReader = new ReactionsReader(scope, props.rtcSession);
-    const {
-      autoLeaveWhenOthersLeft,
-      waitForCallPickup,
-      sendNotificationType,
-      controlledAudioDevices,
-      header,
-      showControls,
-      hideScreensharing,
-      callIntent,
-    } = urlParams;
+    const { autoLeaveWhenOthersLeft, waitForCallPickup, sendNotificationType } =
+      urlParams;
 
     const vm = createCallViewModel$(
       scope,
@@ -141,17 +134,12 @@ export const ActiveCall: FC<ActiveCallProps> = (props) => {
       mediaDevices,
       props.muteStates,
       {
+        ...callViewModelOptionsFromParams(urlParams),
         encryptionSystem: props.e2eeSystem,
         hostBridge,
         autoLeaveWhenOthersLeft,
         waitForCallPickup: waitForCallPickup && sendNotificationType === "ring",
         matrixRTCMode$: matrixRTCModeSetting.value$,
-        controlledAudioDevices,
-        header,
-        showControls,
-        hideScreensharing,
-        sendNotificationType,
-        callIntent,
       },
       reactionsReader.raisedHands$,
       reactionsReader.reactions$,
diff --git a/src/state/CallViewModel/CallViewModel.test.ts b/src/state/CallViewModel/CallViewModel.test.ts
index 7a27fd3e0..c7783d152 100644
--- a/src/state/CallViewModel/CallViewModel.test.ts
+++ b/src/state/CallViewModel/CallViewModel.test.ts
@@ -68,6 +68,8 @@ import {
 } from "./CallViewModelTestUtils.ts";
 import { MatrixRTCMode } from "../../config/ConfigOptions.ts";
 import { initializeWidget } from "../../widget.ts";
+import { computeUrlParams } from "../../UrlParams.ts";
+import { callViewModelOptionsFromParams } from "./CallViewModel.ts";
 
 initializeWidget();
 
@@ -83,9 +85,6 @@ vi.mock("livekit-client/e2ee-worker?worker");
 
 vi.mock("../e2ee/matrixKeyProvider");
 
-const getUrlParams = vi.hoisted(() => vi.fn(() => ({})));
-vi.mock("../UrlParams", () => ({ getUrlParams }));
-
 const getPlatform = vi.hoisted(() => vi.fn(() => "desktop"));
 vi.mock("../../Platform", () => ({
   get platform(): string {
@@ -1701,3 +1700,42 @@ describe.each(modes)("CallViewModel (%s mode)", (mode) => {
     });
   });
 });
+
+describe("callViewModelOptionsFromParams", () => {
+  // The defaults on CallViewModelOptions describe a standalone Element Call, so
+  // a widget caller that drops one of these gets standalone behaviour rather
+  // than an error. These check the whole chain from URL to options, which is
+  // where that went wrong for the SDK.
+  const widgetUrl = (extra: string): string =>
+    `#?widgetId=id&parentUrl=${encodeURIComponent("http://parent")}&${extra}`;
+
+  it("carries an explicitly requested notification type", () => {
+    const params = computeUrlParams("", widgetUrl("sendNotificationType=ring"));
+    expect(callViewModelOptionsFromParams(params).sendNotificationType).toBe(
+      "ring",
+    );
+  });
+
+  it("carries the notification type an intent implies", () => {
+    const params = computeUrlParams("", widgetUrl("intent=start_call_dm"));
+    expect(callViewModelOptionsFromParams(params).sendNotificationType).toBe(
+      "ring",
+    );
+  });
+
+  it("carries hideScreensharing", () => {
+    const params = computeUrlParams("", widgetUrl("hideScreensharing=true"));
+    expect(callViewModelOptionsFromParams(params).hideScreensharing).toBe(true);
+  });
+
+  it("carries controlledAudioDevices and the call intent", () => {
+    const params = computeUrlParams(
+      "",
+      widgetUrl("controlledAudioDevices=true&intent=start_call_voice"),
+    );
+    expect(callViewModelOptionsFromParams(params)).toMatchObject({
+      controlledAudioDevices: true,
+      callIntent: "audio",
+    });
+  });
+});
diff --git a/src/state/CallViewModel/CallViewModel.ts b/src/state/CallViewModel/CallViewModel.ts
index b40a45231..85ba27573 100644
--- a/src/state/CallViewModel/CallViewModel.ts
+++ b/src/state/CallViewModel/CallViewModel.ts
@@ -86,7 +86,7 @@ import { constant, type Behavior } from "../Behavior";
 import { E2eeType } from "../../e2ee/e2eeType";
 import { MatrixKeyProvider } from "../../e2ee/matrixKeyProvider";
 import { type MuteStates } from "../MuteStates";
-import { HeaderStyle } from "../../UrlParams";
+import { HeaderStyle, type UrlParams } from "../../UrlParams";
 import { type ProcessorState } from "../../livekit/TrackProcessorContext";
 import { type HostBridge, nullHostBridge } from "../../HostBridge";
 import {
@@ -216,6 +216,40 @@ export interface CallViewModelOptions {
   toggleScreensharing?: () => void;
 }
 
+/**
+ * The options {@link createCallViewModel$} takes from the parameters Element
+ * Call was started with.
+ *
+ * Callers share this rather than picking the fields out themselves. The
+ * defaults on {@link CallViewModelOptions} describe a standalone Element Call,
+ * so a widget or embedded caller that misses one does not get an error — it
+ * quietly gets standalone behaviour instead.
+ *
+ * Note `autoLeaveWhenOthersLeft` and `waitForCallPickup` are deliberately not
+ * here: unlike these, the view model never read them from the parameters
+ * itself, so they remain the caller's decision.
+ */
+export function callViewModelOptionsFromParams(
+  params: UrlParams,
+): Pick<
+  CallViewModelOptions,
+  | "controlledAudioDevices"
+  | "header"
+  | "showControls"
+  | "hideScreensharing"
+  | "sendNotificationType"
+  | "callIntent"
+> {
+  return {
+    controlledAudioDevices: params.controlledAudioDevices,
+    header: params.header,
+    showControls: params.showControls,
+    hideScreensharing: params.hideScreensharing,
+    sendNotificationType: params.sendNotificationType,
+    callIntent: params.callIntent,
+  };
+}
+
 // Do not play any sounds if the participant count has exceeded this
 // number.
 export const MAX_PARTICIPANT_COUNT_FOR_SOUND = 8;