Example: Placing an outbound call

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{"destination":"+15551234567","callerId":"+15557654321"}

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/**
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 * Voximplant + Gemini Live API connector demo
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 * Scenario: place an outbound PSTN call and bridge it to Gemini Live API.
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 */
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require(Modules.Gemini);
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require(Modules.ApplicationStorage);
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const SYSTEM_PROMPT = `
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You are Voxi, a helpful voice assistant for phone callers.
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Keep responses short and telephony-friendly (usually 1-2 sentences).
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`;
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// -------------------- Gemini Live API settings --------------------
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const CONNECT_CONFIG = {
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    responseModalities: ["AUDIO"],
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    thinkingConfig: {thinkingLevel: "minimal"},
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    systemInstruction: {
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        parts: [{text: SYSTEM_PROMPT}],
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    },
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    inputAudioTranscription: {},
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    outputAudioTranscription: {},
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};
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VoxEngine.addEventListener(AppEvents.Started, async () => {
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    let voiceAIClient;
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    let call;
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    try {
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        // This can be provided when manually running a routing rule in the Control Panel,
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        // or via Management API using the `script_custom_data` parameter.
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        // example: {"destination": "+15551234567","callerId": "+15557654321"}
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        const {destination, callerId} = JSON.parse(VoxEngine.customData());
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        // Place the outbound call
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        call = VoxEngine.callPSTN(destination, callerId);
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        // Alternative outbound paths (uncomment to use):
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        // call = VoxEngine.callUser({username: destination, callerid: callerId});
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        // call = VoxEngine.callSIP(`sip:${destination}@your-sip-domain`, callerId);
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        // call = VoxEngine.callWhatsappUser({number: destination, callerid: callerId});
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        // Termination functions - add cleanup and logging as needed
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        call.addEventListener(CallEvents.Disconnected, VoxEngine.terminate);
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        call.addEventListener(CallEvents.Failed, VoxEngine.terminate);
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        call.addEventListener(CallEvents.Connected, async () => {
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            // call.record({ hd_audio: true, stereo: true });  // Optional: record the call
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            voiceAIClient = await Gemini.createLiveAPIClient({
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                apiKey: (await ApplicationStorage.get("GEMINI_API_KEY")).value,
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                model: "gemini-3.1-flash-live-preview",
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                backend: Gemini.Backend.GEMINI_API,
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                connectConfig: CONNECT_CONFIG,
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                onWebSocketClose: () => {
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                    Logger.write(`===Gemini.WebSocket.Close===`);
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                    VoxEngine.terminate();
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                },
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            });
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            voiceAIClient.addEventListener(Gemini.LiveAPIEvents.SetupComplete, () => {
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                VoxEngine.sendMediaBetween(call, voiceAIClient);
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                voiceAIClient.sendRealtimeInput({
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                    text: "Say hello and ask how you can help.",
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                });
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            });
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            // Capture transcripts + handle barge-in
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            voiceAIClient.addEventListener(Gemini.LiveAPIEvents.ServerContent, (event) => {
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                const payload = event?.data?.payload || {};
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                if (payload.inputTranscription?.text) {
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                    Logger.write(`===USER=== ${payload.inputTranscription.text}`);
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                }
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                if (payload.outputTranscription?.text) {
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                    Logger.write(`===AGENT=== ${payload.outputTranscription.text}`);
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                }
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                if (payload.interrupted) {
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                    Logger.write("===BARGE-IN=== Gemini.LiveAPIEvents.ServerContent");
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                    voiceAIClient.clearMediaBuffer();
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                }
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            });
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            // Log all Gemini events for illustration/debugging
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            [
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                Gemini.LiveAPIEvents.SetupComplete,
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                Gemini.LiveAPIEvents.ServerContent,
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                Gemini.LiveAPIEvents.ToolCall,
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                Gemini.LiveAPIEvents.ToolCallCancellation,
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                Gemini.LiveAPIEvents.ConnectorInformation,
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                Gemini.LiveAPIEvents.Unknown,
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                Gemini.Events.WebSocketMediaStarted,
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                Gemini.Events.WebSocketMediaEnded,
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            ].forEach((eventName) => {
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                voiceAIClient.addEventListener(eventName, (event) => {
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                    Logger.write(`===${event.name}===`);
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                    if (event?.data) Logger.write(JSON.stringify(event.data));
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                });
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            });
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        });
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    } catch (error) {
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        Logger.write("===SOMETHING_WENT_WRONG===");
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        Logger.write(error);
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        voiceAIClient?.close();
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        VoxEngine.terminate();
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    }
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});