diff --git a/extensions/openai/realtime-transcription-provider.test.ts b/extensions/openai/realtime-transcription-provider.test.ts
index 6ee64399cd1..4e5eb9a37d1 100644
--- a/extensions/openai/realtime-transcription-provider.test.ts
+++ b/extensions/openai/realtime-transcription-provider.test.ts
@@ -54,7 +54,6 @@ type SentRealtimeEvent = {
   type: string;
   audio?: string;
   session?: {
-    type?: string;
     audio?: {
       input?: {
         format?: { type?: string };
@@ -180,7 +179,6 @@ describe("buildOpenAIRealtimeTranscriptionProvider", () => {
       {
         type: "transcription_session.update",
         session: {
-          type: "transcription",
           audio: {
             input: {
               format: { type: "audio/pcmu" },
@@ -209,7 +207,6 @@ describe("buildOpenAIRealtimeTranscriptionProvider", () => {
       {
         type: "transcription_session.update",
         session: {
-          type: "transcription",
           audio: {
             input: {
               format: { type: "audio/pcmu" },
diff --git a/extensions/openai/realtime-transcription-provider.ts b/extensions/openai/realtime-transcription-provider.ts
index 3a276a6dbfd..8c68c8650d5 100644
--- a/extensions/openai/realtime-transcription-provider.ts
+++ b/extensions/openai/realtime-transcription-provider.ts
@@ -149,7 +149,6 @@ function createOpenAIRealtimeTranscriptionSession(
       transport.sendJson({
         type: "transcription_session.update",
         session: {
-          type: "transcription",
           audio: {
             input: {
               format: {