diff --git a/src/components/ha-assist-chat.ts b/src/components/ha-assist-chat.ts
index ce069a94ee..3f4c3f75a4 100644
--- a/src/components/ha-assist-chat.ts
+++ b/src/components/ha-assist-chat.ts
@@ -509,7 +509,7 @@ export class HaAssistChat extends LitElement {
         this.requestUpdate("_conversation");
       },
       processEvent: (event: PipelineRunEvent) => {
-        if (event.type === "intent-progress") {
+        if (event.type === "intent-progress" && event.data.chat_log_delta) {
           const delta = event.data.chat_log_delta;
 
           // new message
diff --git a/src/data/assist_pipeline.ts b/src/data/assist_pipeline.ts
index 8c6d10949a..e2b1e7a71b 100644
--- a/src/data/assist_pipeline.ts
+++ b/src/data/assist_pipeline.ts
@@ -134,7 +134,8 @@ export interface ConversationChatLogToolResultDelta {
 interface PipelineIntentProgressEvent extends PipelineEventBase {
   type: "intent-progress";
   data: {
-    chat_log_delta:
+    tts_start_streaming?: boolean;
+    chat_log_delta?:
       | Partial<ConversationChatLogAssistantDelta>
       // These always come in 1 chunk
       | ConversationChatLogToolResultDelta;