Sync from internal repo (2026/06/04)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "assemblyai",
-  "version": "4.34.0",
+  "version": "4.34.3",
   "description": "The AssemblyAI JavaScript SDK provides an easy-to-use interface for interacting with the AssemblyAI API, which supports async and real-time transcription, as well as the latest LeMUR models.",
   "engines": {
     "node": ">=18"

src/services/streaming/service.ts

@@ -262,6 +262,10 @@ export class StreamingTranscriber {
       searchParams.set("prompt", this.params.prompt);
     }
 
+    if (this.params.agentContext) {
+      searchParams.set("agent_context", this.params.agentContext);
+    }
+
     if (this.params.filterProfanity) {
       searchParams.set(
         "filter_profanity",
@@ -274,7 +278,9 @@ export class StreamingTranscriber {
         "[Deprecation Warning] The speech model `u3-pro` is deprecated and will be removed in a future release. Please use `u3-rt-pro` instead.",
       );
     }
-    searchParams.set("speech_model", this.params.speechModel.toString());
+    if (this.params.speechModel !== undefined) {
+      searchParams.set("speech_model", this.params.speechModel.toString());
+    }
 
     if (this.params.languageDetection !== undefined) {
       searchParams.set(
@@ -389,6 +395,10 @@ export class StreamingTranscriber {
       searchParams.set("redact_pii_sub", this.params.redactPiiSub);
     }
 
+    if (this.params.mode !== undefined) {
+      searchParams.set("mode", this.params.mode);
+    }
+
     if (this.params.llmGateway !== undefined) {
       searchParams.set("llm_gateway", JSON.stringify(this.params.llmGateway));
     }

src/types/streaming/index.ts

@@ -91,7 +91,8 @@ export type StreamingTranscriberParams = {
   keyterms?: string[];
   keytermsPrompt?: string[];
   prompt?: string;
-  speechModel: StreamingSpeechModel;
+  agentContext?: string;
+  speechModel?: StreamingSpeechModel;
   languageDetection?: boolean;
   domain?: StreamingDomain;
   inactivityTimeout?: number;
@@ -107,6 +108,7 @@ export type StreamingTranscriberParams = {
   redactPii?: boolean;
   redactPiiPolicies?: StreamingPiiPolicy[];
   redactPiiSub?: StreamingPiiSubstitution;
+  mode?: StreamingMode;
   llmGateway?: LLMGatewayConfig;
   webhookUrl?: string;
   webhookAuthHeaderName?: string;
@@ -165,11 +167,14 @@ export type StreamingSpeechModel =
   | "universal-streaming-english"
   | "universal-streaming-multilingual"
   | "u3-rt-pro"
+  | "u3-rt-pro-beta-1"
   | "whisper-rt"
   | "u3-pro";
 
 export type StreamingDomain = "medical-v1";
 
+export type StreamingMode = "max_accuracy" | "min_latency" | "balanced";
+
 export type VoiceFocusModel = "near-field" | "far-field";
 
 export type StreamingPiiSubstitution = "hash" | "entity_name";
@@ -330,6 +335,7 @@ export type StreamingUpdateConfiguration = {
   format_turns?: boolean;
   keyterms_prompt?: string[];
   prompt?: string;
+  agent_context?: string;
   filter_profanity?: boolean;
   interruption_delay?: number;
   turn_left_pad_ms?: number;

tests/unit/streaming.test.ts

@@ -204,6 +204,37 @@ describe("streaming", () => {
     );
   });
 
+  it("should include agent_context in updateConfiguration message", async () => {
+    rt.updateConfiguration({ agent_context: "What is your account number?" });
+    await expect(server).toReceiveMessage(
+      JSON.stringify({
+        type: "UpdateConfiguration",
+        agent_context: "What is your account number?",
+      }),
+    );
+  });
+
+  it("should include agent_context in connection URL", async () => {
+    await cleanup();
+    WS.clean();
+
+    const wsUrl =
+      `${websocketBaseUrl}?token=123&sample_rate=16000` +
+      `&agent_context=${encodeURIComponent("What is your account number?")}` +
+      `&speech_model=u3-rt-pro`;
+    server = new WS(wsUrl);
+    rt = new StreamingTranscriber({
+      websocketBaseUrl,
+      token: "123",
+      sampleRate: 16_000,
+      speechModel: "u3-rt-pro",
+      agentContext: "What is your account number?",
+    });
+    onOpen = jest.fn();
+    rt.on("open", onOpen);
+    await connect(rt, server);
+  });
+
   it("should include turn_left_pad_ms in connection URL", async () => {
     await cleanup();
     WS.clean();
@@ -254,6 +285,24 @@ describe("streaming", () => {
     await connect(rt, server);
   });
 
+  it("should include mode in connection URL", async () => {
+    await cleanup();
+    WS.clean();
+
+    const wsUrl = `${websocketBaseUrl}?token=123&sample_rate=16000&speech_model=u3-rt-pro&mode=max_accuracy`;
+    server = new WS(wsUrl);
+    rt = new StreamingTranscriber({
+      websocketBaseUrl,
+      token: "123",
+      sampleRate: 16_000,
+      speechModel: "u3-rt-pro",
+      mode: "max_accuracy",
+    });
+    onOpen = jest.fn();
+    rt.on("open", onOpen);
+    await connect(rt, server);
+  });
+
   it("should include whisper-rt speech model in connection URL", async () => {
     await cleanup();
     WS.clean();