微信扫一扫Vapi Assistant Creation
Create fully configured voice AI assistants using the Vapi API. Assistants combine a language model, voice, and transcriber to handle real-time phone and web conversations.
Setup: Ensure
VAPI_API_KEYis set. See thesetup-api-keyskill if needed.
Quick Start
cURL
curl -X POST https://api.vapi.ai/assistant \
-H "Authorization: Bearer $VAPI_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"name": "Support Assistant",
"firstMessage": "Hello! How can I help you today?",
"model": {
"provider": "openai",
"model": "gpt-4.1",
"messages": [
{
"role": "system",
"content": "You are a friendly phone support assistant. Keep responses concise and under 30 words."
}
]
},
"voice": {
"provider": "vapi",
"voiceId": "Elliot"
},
"transcriber": {
"provider": "deepgram",
"model": "nova-3",
"language": "en"
}
}'
TypeScript (Server SDK)
import { VapiClient } from "@vapi-ai/server-sdk";
const vapi = new VapiClient({ token: process.env.VAPI_API_KEY! });
const assistant = await vapi.assistants.create({
name: "Support Assistant",
firstMessage: "Hello! How can I help you today?",
model: {
provider: "openai",
model: "gpt-4.1",
messages: [
{
role: "system",
content: "You are a friendly phone support assistant. Keep responses concise and under 30 words.",
},
],
},
voice: {
provider: "vapi",
voiceId: "Elliot",
},
transcriber: {
provider: "deepgram",
model: "nova-3",
language: "en",
},
});
console.log("Assistant created:", assistant.id);
Python
import requests
import os
response = requests.post(
"https://api.vapi.ai/assistant",
headers={
"Authorization": f"Bearer {os.environ['VAPI_API_KEY']}",
"Content-Type": "application/json",
},
json={
"name": "Support Assistant",
"firstMessage": "Hello! How can I help you today?",
"model": {
"provider": "openai",
"model": "gpt-4.1",
"messages": [
{
"role": "system",
"content": "You are a friendly phone support assistant. Keep responses concise and under 30 words.",
}
],
},
"voice": {"provider": "vapi", "voiceId": "Elliot"},
"transcriber": {"provider": "deepgram", "model": "nova-3", "language": "en"},
},
)
assistant = response.json()
print(f"Assistant created: {assistant['id']}")
Core Configuration
Model (required)
The language model powering the assistant's intelligence.
| Provider | Models | Notes |
|----------|--------|-------|
| openai | gpt-4o, gpt-4o-mini, gpt-4-turbo | Most popular, best tool calling |
| anthropic | claude-3-5-sonnet-20241022, claude-3-5-haiku-20241022 | Strong reasoning |
| google | gemini-1.5-pro, gemini-1.5-flash | Multimodal capable |
| groq | llama-3.1-70b-versatile, llama-3.1-8b-instant | Ultra-fast inference |
| deepinfra | meta-llama/Meta-Llama-3.1-70B-Instruct | Open-source models |
| openrouter | Various | Access 100+ models |
| perplexity | llama-3.1-sonar-large-128k-online | Web-connected |
| together-ai | Various open-source | Cost-effective |
{
"model": {
"provider": "openai",
"model": "gpt-4.1",
"temperature": 0.7,
"maxTokens": 1000,
"messages": [
{
"role": "system",
"content": "Your system prompt here. Define the assistant's personality, rules, and behavior."
}
]
}
}
Voice
The text-to-speech voice for the assistant.
| Provider | Popular Voices | Notes |
|----------|---------------|-------|
| vapi | Elliot, Lily, Rohan, Paola, Kian | Vapi's optimized voices, lowest latency |
| 11labs | Use voice IDs from ElevenLabs | High quality, many voices |
| playht | Use voice IDs from PlayHT | Expressive voices |
| cartesia | Use voice IDs from Cartesia | Fast, high quality |
| openai | alloy, echo, fable, onyx, nova, shimmer | OpenAI TTS voices |
| azure | Azure voice names | Enterprise-grade |
| deepgram | aura-asteria-en, aura-luna-en | Low latency |
| rime-ai | Use voice IDs from Rime | Specialized voices |
{
"voice": {
"provider": "vapi",
"voiceId": "Elliot"
}
}
Transcriber
The speech-to-text engine for understanding callers.
| Provider | Models | Notes |
|----------|--------|-------|
| deepgram | nova-3, nova-2 | Fastest, most accurate |
| google | latest_long, latest_short | Google Cloud STT |
| gladia | fast, accurate | European provider |
| assembly-ai | best, nano | High accuracy |
| speechmatics | Various | Enterprise STT |
| talkscriber | Default | Specialized |
{
"transcriber": {
"provider": "deepgram",
"model": "nova-3",
"language": "en",
"keywords": ["Vapi:2", "AI:1"]
}
}
The keywords field boosts recognition of specific words (word:boost format, boost 1-10).
Behavior Configuration
First Message
{
"firstMessage": "Hello! Thanks for calling Acme Corp. How can I help you today?",
"firstMessageMode": "assistant-speaks-first"
}
firstMessageMode options:
"assistant-speaks-first"— Assistant greets immediately (default)"assistant-waits-for-user"— Assistant waits for caller to speak first"assistant-speaks-first-with-model-generated-message"— LLM generates the greeting
Background Sound
{
"backgroundSound": "office"
}
Options: "off", "office", "static"
Backchanneling
Enable natural conversational acknowledgments ("uh-huh", "I see"):
{
"backgroundDenoisingEnabled": true,
"backchannelingEnabled": true
}
HIPAA Compliance
{
"hipaaEnabled": true
}
When enabled, Vapi won't store call recordings or transcripts.
Adding Tools
Attach tools so the assistant can take actions during calls.
Using saved tool IDs
{
"model": {
"provider": "openai",
"model": "gpt-4.1",
"toolIds": ["tool-id-1", "tool-id-2"],
"messages": [{"role": "system", "content": "..."}]
}
}
Inline tool definition
{
"model": {
"provider": "openai",
"model": "gpt-4.1",
"tools": [
{
"type": "function",
"function": {
"name": "check_availability",
"description": "Check appointment availability for a given date",
"parameters": {
"type": "object",
"properties": {
"date": {
"type": "string",
"description": "Date in YYYY-MM-DD format"
}
},
"required": ["date"]
}
},
"server": {
"url": "https://your-server.com/api/tools"
}
}
],
"messages": [{"role": "system", "content": "..."}]
}
}
Hooks
Automate actions when specific call events occur. See hooks reference for details.
{
"hooks": [
{
"on": "customer.speech.timeout",
"options": {
"timeoutSeconds": 10,
"triggerMaxCount": 3
},
"do": [
{
"type": "say",
"exact": "Are you still there?"
}
]
},
{
"on": "call.ending",
"filters": [
{
"type": "oneOf",
"key": "call.endedReason",
"oneOf": ["pipeline-error"]
}
],
"do": [
{
"type": "tool",
"tool": {
"type": "transferCall",
"destinations": [
{
"type": "number",
"number": "+1234567890"
}
]
}
}
]
}
]
}
Managing Assistants
List
curl https://api.vapi.ai/assistant \
-H "Authorization: Bearer $VAPI_API_KEY"
Get
curl https://api.vapi.ai/assistant/{id} \
-H "Authorization: Bearer $VAPI_API_KEY"
Update
curl -X PATCH https://api.vapi.ai/assistant/{id} \
-H "Authorization: Bearer $VAPI_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"firstMessage": "Updated greeting!"
}'
Delete
curl -X DELETE https://api.vapi.ai/assistant/{id} \
-H "Authorization: Bearer $VAPI_API_KEY"
Common Patterns
Customer Support Agent
{
"name": "Customer Support",
"firstMessage": "Thank you for calling! How can I assist you today?",
"model": {
"provider": "openai",
"model": "gpt-4.1",
"messages": [
{
"role": "system",
"content": "You are a helpful customer support agent for Acme Corp. Be empathetic, concise, and solution-oriented. If you cannot resolve an issue, offer to transfer to a human agent. Keep responses under 30 words."
}
]
},
"voice": { "provider": "vapi", "voiceId": "Lily" },
"transcriber": { "provider": "deepgram", "model": "nova-3", "language": "en" },
"backchannelingEnabled": true
}
Appointment Scheduler
{
"name": "Appointment Scheduler",
"firstMessage": "Hi there! I can help you schedule an appointment. What date works best for you?",
"model": {
"provider": "openai",
"model": "gpt-4.1",
"messages": [
{
"role": "system",
"content": "You are an appointment scheduling assistant. Collect the customer's preferred date, time, and service type. Confirm details before booking. Be friendly and efficient."
}
],
"tools": [
{
"type": "function",
"function": {
"name": "book_appointment",
"description": "Book an appointment for the given date, time, and service",
"parameters": {
"type": "object",
"properties": {
"date": { "type": "string", "description": "YYYY-MM-DD" },
"time": { "type": "string", "description": "HH:MM in 24h format" },
"service": { "type": "string", "description": "Type of service" },
"name": { "type": "string", "description": "Customer name" }
},
"required": ["date", "time", "service", "name"]
}
},
"server": { "url": "https://your-server.com/api/book" }
}
]
},
"voice": { "provider": "vapi", "voiceId": "Paola" },
"transcriber": { "provider": "deepgram", "model": "nova-3", "language": "en" }
}
Multilingual Agent
{
"name": "Multilingual Support",
"firstMessage": "Hello! How can I help you? / Hola! Como puedo ayudarte?",
"model": {
"provider": "openai",
"model": "gpt-4.1",
"messages": [
{
"role": "system",
"content": "You are a multilingual support assistant. Detect the caller's language and respond in the same language. You support English and Spanish."
}
]
},
"voice": { "provider": "vapi", "voiceId": "Paola" },
"transcriber": { "provider": "deepgram", "model": "nova-3", "language": "multi" }
}
References
- Hooks Configuration — Complete hook events and actions
- Voice & Model Providers — All supported providers and models
- Vapi API Docs — Official documentation
Additional Resources
This skills repository includes a Vapi documentation MCP server (vapi-docs) that gives your AI agent access to the full Vapi knowledge base. Use the searchDocs tool to look up anything beyond what this skill covers — advanced configuration, troubleshooting, SDK details, and more.
Auto-configured: If you cloned or installed these skills, the MCP server is already configured via .mcp.json (Claude Code), .cursor/mcp.json (Cursor), or .vscode/mcp.json (VS Code Copilot).
Manual setup: If your agent doesn't auto-detect the config, run:
claude mcp add vapi-docs -- npx -y mcp-remote https://docs.vapi.ai/_mcp/server
See the README for full setup instructions across all supported agents.