Example: Function calling

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agentsClient.addEventListener(ElevenLabs.AgentsEvents.ClientToolCall, (event) => {
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  const payload = event?.data?.payload || event?.data || {};
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  const toolName = payload.tool_name || payload.toolName || payload.name;
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  const toolCallId = payload.tool_call_id || payload.toolCallId || payload.id;
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  if (toolName !== "get_weather") return;
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  const result = { location: "San Francisco", temperature_f: 72, condition: "sunny" };
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  agentsClient.clientToolResult({
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    tool_call_id: toolCallId,
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    tool_name: toolName,
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    result,
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  });
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});

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agentsClient.addEventListener(ElevenLabs.AgentsEvents.Interruption, () => {
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  agentsClient.clearMediaBuffer();
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});

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/**
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 * Voximplant + ElevenLabs Agents connector demo
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 * Scenario: answer an incoming call and handle ElevenLabs tool calls.
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 */
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require(Modules.ElevenLabs);
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const TOOL_NAME = "get_weather";
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// Optional. Leave empty to use the default ElevenLabs Agents endpoint.
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const ELEVENLABS_BASE_URL = "";
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VoxEngine.addEventListener(AppEvents.CallAlerting, async ({call}) => {
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    let voiceAIClient;
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    call.addEventListener(CallEvents.Disconnected, () => VoxEngine.terminate());
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    call.addEventListener(CallEvents.Failed, () => VoxEngine.terminate());
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    try {
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        call.answer();
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        // Create client and connect to ElevenLabs Agents
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        const agentsClientParameters = {
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            xiApiKey: VoxEngine.getSecretValue("ELEVENLABS_API_KEY"),
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            agentId: VoxEngine.getSecretValue("ELEVENLABS_AGENT_ID"),
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            onWebSocketClose: (event) => {
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                Logger.write("===ElevenLabs.WebSocket.Close===");
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                if (event) Logger.write(JSON.stringify(event));
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                VoxEngine.terminate();
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            },
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        };
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        if (ELEVENLABS_BASE_URL) {
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            agentsClientParameters.baseUrl = ELEVENLABS_BASE_URL;
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        }
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        voiceAIClient = await ElevenLabs.createAgentsClient(agentsClientParameters);
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        // Bridge media between the call and ElevenLabs Agents
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        VoxEngine.sendMediaBetween(call, voiceAIClient);
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        // ---------------------- Event handlers -----------------------
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        // Barge-in: keep conversation responsive
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        voiceAIClient.addEventListener(ElevenLabs.AgentsEvents.Interruption, () => {
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            Logger.write("===BARGE-IN: ElevenLabs.AgentsEvents.Interruption===");
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            voiceAIClient.clearMediaBuffer();
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        });
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        // Handle user transcripts
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        voiceAIClient.addEventListener(ElevenLabs.AgentsEvents.UserTranscript, (event) => {
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            const payload = event?.data?.payload || event?.data || {};
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            const text = payload.text || payload.transcript || payload.user_transcript;
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            if (text) {
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                Logger.write(`===USER=== ${text}`);
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            } else {
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                Logger.write("===USER_TRANSCRIPT===");
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                Logger.write(JSON.stringify(payload));
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            }
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        });
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        // Handle tool calls
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        voiceAIClient.addEventListener(ElevenLabs.AgentsEvents.ClientToolCall, (event) => {
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            const payload = event?.data?.payload || event?.data || {};
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            const toolName = payload.tool_name || payload.toolName || payload.name;
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            const toolCallId = payload.tool_call_id || payload.toolCallId || payload.id;
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            if (!toolName || !toolCallId) {
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                Logger.write("===TOOL_CALL_MISSING_FIELDS===");
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                Logger.write(JSON.stringify(payload));
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                return;
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            }
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            let args = {};
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            const rawArgs = payload.parameters || payload.args || payload.arguments;
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            if (typeof rawArgs === "string") {
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                try {
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                    args = JSON.parse(rawArgs);
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                } catch (error) {
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                    Logger.write("===TOOL_ARGS_PARSE_ERROR===");
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                    Logger.write(rawArgs);
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                    Logger.write(error);
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                }
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            } else if (rawArgs && typeof rawArgs === "object") {
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                args = rawArgs;
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            }
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            if (toolName !== TOOL_NAME) {
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                voiceAIClient.clientToolResult({
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                    tool_call_id: toolCallId,
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                    tool_name: toolName,
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                    result: {error: `Unhandled tool: ${toolName}`},
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                });
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                return;
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            }
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            const location = args.location || "Unknown";
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            const result = {
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                location,
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                temperature_f: 72,
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                condition: "sunny",
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            };
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            voiceAIClient.clientToolResult({
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                tool_call_id: toolCallId,
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                tool_name: toolName,
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                result,
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            });
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        });
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        voiceAIClient.addEventListener(ElevenLabs.AgentsEvents.AgentResponse, (event) => {
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            const payload = event?.data?.payload || event?.data || {};
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            const text = payload.text || payload.response || payload.agent_response;
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            if (text) {
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                Logger.write(`===AGENT=== ${text}`);
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            } else {
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                Logger.write("===AGENT_RESPONSE===");
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                Logger.write(JSON.stringify(payload));
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            }
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        });
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        // Consolidated "log-only" handlers - key ElevenLabs/VoxEngine debugging events
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        [
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            ElevenLabs.AgentsEvents.ConversationInitiationMetadata,
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            ElevenLabs.AgentsEvents.AgentResponseCorrection,
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            ElevenLabs.AgentsEvents.ContextualUpdate,
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            ElevenLabs.AgentsEvents.AgentToolResponse,
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            ElevenLabs.AgentsEvents.VadScore,
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            ElevenLabs.AgentsEvents.Ping,
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            ElevenLabs.AgentsEvents.HTTPResponse,
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            ElevenLabs.AgentsEvents.WebSocketError,
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            ElevenLabs.AgentsEvents.ConnectorInformation,
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            ElevenLabs.AgentsEvents.Unknown,
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            ElevenLabs.Events.WebSocketMediaStarted,
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            ElevenLabs.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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    } catch (error) {
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        Logger.write("===UNHANDLED_ERROR===");
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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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});