Vapi

npm install @vapi-ai/web

npm install @vapi-ai/server-sdk

pip install vapi_server_sdk

curl -sSL https://vapi.ai/install.sh | bash

import Vapi from "@vapi-ai/web";

const vapi = new Vapi("YOUR_PUBLIC_API_KEY");

const assistant = await vapi.assistants.create({
  name: "Customer Support Agent",
  firstMessage: "Hello! How can I help you today?",
  model: {
    provider: "openai",
    model: "gpt-4o",
    temperature: 0.7,
    messages: [
      {
        role: "system",
        content:
          "You are a friendly customer support agent. Help users with their orders and account questions.",
      },
    ],
  },
  voice: {
    provider: "11labs",
    voiceId: "21m00Tcm4TlvDq8ikWAM",
  },
});

from vapi import Vapi
import os

vapi = Vapi(token=os.getenv("VAPI_API_KEY"))

assistant = vapi.assistants.create(
    name="Customer Support Agent",
    first_message="Hello! How can I help you today?",
    model={
        "provider": "openai",
        "model": "gpt-4o",
        "temperature": 0.7,
        "messages": [
            {
                "role": "system",
                "content": "You are a friendly customer support agent. Help users with their orders and account questions.",
            }
        ],
    },
    voice={
        "provider": "11labs",
        "voiceId": "21m00Tcm4TlvDq8ikWAM",
    },
)

import Vapi from "@vapi-ai/web";

const vapi = new Vapi("YOUR_PUBLIC_API_KEY");

vapi.start("YOUR_ASSISTANT_ID");

vapi.on("call-start", () => {
  console.log("Call connected");
});

vapi.on("call-end", () => {
  console.log("Call ended");
});

vapi.on("message", (message) => {
  if (message.type === "transcript") {
    console.log(`${message.role}: ${message.transcript}`);
  }
});

vapi.on("error", (error) => {
  console.error("Call error:", error);
});

from vapi import Vapi
import os

vapi = Vapi(token=os.getenv("VAPI_API_KEY"))

call = vapi.calls.create(
    phone_number_id="YOUR_PHONE_NUMBER_ID",
    customer={"number": "+1234567890"},
    assistant_id="YOUR_ASSISTANT_ID",
)

print(f"Call started: {call.id}")

curl -X POST 'https://api.vapi.ai/tool' \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -d '{
    "type": "function",
    "function": {
      "name": "get_order_status",
      "description": "Check the current status of a customer order",
      "parameters": {
        "type": "object",
        "properties": {
          "order_id": {
            "type": "string",
            "description": "The unique order identifier"
          }
        },
        "required": ["order_id"]
      }
    },
    "server": {
      "url": "https://your-api.com/webhook/vapi"
    }
  }'

curl -X PATCH 'https://api.vapi.ai/assistant/ASSISTANT_ID' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "model": {
      "provider": "openai",
      "model": "gpt-4o",
      "toolIds": ["your-tool-id"]
    }
  }'

vapi tool list

vapi tool get <tool-id>

vapi tool create

vapi tool test <tool-id>

vapi tool delete <tool-id>

{
  "message": {
    "type": "tool-calls",
    "toolCallList": [
      {
        "id": "toolu_01DTPAzUm5Gk3zxrpJ969oMF",
        "name": "get_order_status",
        "arguments": {
          "order_id": "ORD-12345"
        }
      }
    ]
  }
}

{
  "results": [
    {
      "toolCallId": "toolu_01DTPAzUm5Gk3zxrpJ969oMF",
      "result": "Order ORD-12345 is currently being shipped. Expected delivery: tomorrow."
    }
  ]
}

import express from "express";

const app = express();
app.use(express.json());

app.post("/webhook/vapi", async (req, res) => {
  const { message } = req.body;

  if (message.type === "tool-calls") {
    const results = await Promise.all(
      message.toolCallList.map(async (toolCall) => {
        if (toolCall.name === "get_order_status") {
          const order = await db.orders.findById(
            toolCall.arguments.order_id
          );
          return {
            toolCallId: toolCall.id,
            result: `Order ${order.id}: ${order.status}. ${order.trackingInfo}`,
          };
        }

        if (toolCall.name === "book_appointment") {
          const booking = await calendar.createEvent(
            toolCall.arguments
          );
          return {
            toolCallId: toolCall.id,
            result: `Appointment booked for ${booking.date} at ${booking.time}.`,
          };
        }

        return {
          toolCallId: toolCall.id,
          result: "Unknown tool",
        };
      })
    );

    return res.json({ results });
  }

  res.json({ received: true });
});

app.listen(3000);

from flask import Flask, request, jsonify

app = Flask(__name__)

@app.route("/webhook/vapi", methods=["POST"])
def handle_webhook():
    message = request.json.get("message", {})

    if message.get("type") == "tool-calls":
        results = []
        for tool_call in message.get("toolCallList", []):
            if tool_call["name"] == "get_order_status":
                order = db.orders.find_by_id(tool_call["arguments"]["order_id"])
                results.append({
                    "toolCallId": tool_call["id"],
                    "result": f"Order {order.id}: {order.status}. {order.tracking_info}",
                })

            elif tool_call["name"] == "book_appointment":
                booking = calendar.create_event(tool_call["arguments"])
                results.append({
                    "toolCallId": tool_call["id"],
                    "result": f"Appointment booked for {booking.date} at {booking.time}.",
                })

        return jsonify({"results": results})

    return jsonify({"received": True})

if __name__ == "__main__":
    app.run(port=3000)

vapi listen --forward-to localhost:3000/tools/webhook

const assistant = await vapi.assistants.create({
  name: "Support Agent",
  firstMessage: "Hi! Welcome to Acme Support. How can I help you?",
  model: {
    provider: "openai",
    model: "gpt-4o",
    messages: [
      {
        role: "system",
        content: `You are a customer support agent for Acme Corp.
You can check order status, process returns, and answer product questions.
Always be friendly and professional. If you cannot resolve an issue,
offer to transfer to a human agent.`,
      },
    ],
    toolIds: ["order-status-tool", "return-tool", "transfer-tool"],
  },
  voice: {
    provider: "11labs",
    voiceId: "21m00Tcm4TlvDq8ikWAM",
  },
});

const assistant = await vapi.assistants.create({
  name: "Booking Agent",
  firstMessage: "Hello! I can help you schedule an appointment. What day works best for you?",
  model: {
    provider: "openai",
    model: "gpt-4o",
    messages: [
      {
        role: "system",
        content: `You are an appointment scheduling assistant for a dental clinic.
Collect: patient name, preferred date/time, reason for visit.
Check availability using the check_slots tool before confirming.
Always confirm the final booking details before saving.`,
      },
    ],
    toolIds: ["check-slots-tool", "book-appointment-tool"],
  },
  voice: {
    provider: "11labs",
    voiceId: "pNInz6obpgDQGcFmaJgB",
  },
});

const assistant = await vapi.assistants.create({
  name: "Sales Qualifier",
  firstMessage:
    "Hi! Thanks for your interest in our product. I'd love to learn more about your needs.",
  model: {
    provider: "anthropic",
    model: "claude-sonnet-4-5-20250514",
    messages: [
      {
        role: "system",
        content: `You are a sales qualification agent.
Ask about: company size, current solution, budget range, timeline.
Score the lead as hot/warm/cold based on responses.
Save qualification data using the save_lead tool.
If the lead is hot, offer to schedule a demo with a sales rep.`,
      },
    ],
    toolIds: ["save-lead-tool", "schedule-demo-tool"],
  },
  voice: {
    provider: "playht",
    voiceId: "jennifer",
  },
});

import { useState } from "react";
import Vapi from "@vapi-ai/web";

const vapi = new Vapi("YOUR_PUBLIC_API_KEY");

export function VoiceAssistant() {
  const [isActive, setIsActive] = useState(false);
  const [transcript, setTranscript] = useState<string[]>([]);

  const startCall = async () => {
    setIsActive(true);
    await vapi.start("YOUR_ASSISTANT_ID");
  };

  const endCall = () => {
    vapi.stop();
    setIsActive(false);
  };

  vapi.on("message", (message) => {
    if (message.type === "transcript" && message.transcriptType === "final") {
      setTranscript((prev) => [
        ...prev,
        `${message.role}: ${message.transcript}`,
      ]);
    }
  });

  return (
    <div className="flex flex-col items-center gap-4 p-6">
      <button
        onClick={isActive ? endCall : startCall}
        className={`px-6 py-3 rounded-full font-medium ${
          isActive
            ? "bg-red-500 hover:bg-red-600 text-white"
            : "bg-blue-500 hover:bg-blue-600 text-white"
        }`}
      >
        {isActive ? "End Call" : "Start Call"}
      </button>
      <div className="w-full max-w-md space-y-2">
        {transcript.map((line, i) => (
          <p key={i} className="text-sm text-gray-700 dark:text-gray-300">
            {line}
          </p>
        ))}
      </div>
    </div>
  );
}