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AI & Machine Learning

Vapi is the platform to build, test and deploy voice agents in minutes rather than months.

llms.txt

Vapi

Instructions for AI Agents

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Docs

Introduction: Build voice AI agents that can make and receive phone calls
Phone calls: Learn to make your first phone call with a voice agent
Web calls: Build voice interfaces and backend integrations using Vapi's Web and Server SDKs
Guides: Explore real-world, cloneable examples to build voice agents with Assistants and Squads
Composer: Build and configure voice AI agents through natural conversation
Vapi CLI: Command-line interface for building voice AI applications faster
Assistants quickstart: Build your first assistant and make a phone call in minutes
Transient vs permanent configurations: Learn to choose between inline and stored assistant configurations
Variables: Personalize assistant messages with dynamic and default variables
Multilingual support: Configure multilingual voice AI agents with automatic language detection, cross-language conversation, and localized voices
Personalization with user information: Add customer-specific information to your voice assistant conversations
Voice formatting plan: Format LLM output for natural-sounding speech
Flush syntax: Force immediate voice transmission with VAPI's flush syntax for real-time interactions
Background messages: Silently update chat history with background messages
Idle messages: Keep users engaged during conversation pauses
Assistant hooks: Automate actions on call events and interruptions
Background speech denoising: Filter out noise and background speech while users are talking
Pronunciation dictionaries: Control how your AI assistant pronounces specific words and phrases
Email address reading: Get your voice agent to collect, read back, and confirm email addresses clearly
Speech configuration: Control when your assistant starts and stops speaking
Voice pipeline configuration: Complete guide to configuring VAPI's voice pipeline for optimal conversation timing and interruption handling
Voice fallback configuration: Configure fallback voices that activate automatically if your primary voice fails.
Transcriber fallback configuration: Configure fallback transcribers that activate automatically if your primary transcriber fails.
OpenAI Realtime: Build voice assistants with OpenAI's native speech-to-speech models for ultra-low latency conversations
Provider Keys: Bring your own API keys to Vapi.
Introduction to Tools: Extend your assistant's capabilities with powerful function calling tools.
Default Tools: Adding Transfer Call, End Call, Dial Keypad, and API Request capabilities to your assistants.
Voicemail Tool: Learn how to use the assistant-controlled voicemail tool for flexible voicemail handling
Custom Tools: Learn how to create and configure Custom Tools for use by your Vapi assistants.
Code Tool: Execute custom TypeScript code directly within your assistant without setting up a server.
Client-side Tools (Web SDK): Handle tool-calls in the browser without a server URL
Tool rejection plan: Prevent unintended tool calls using conditions based on conversation state
Static variables and aliases: Inject server-controlled values into tool calls without LLM involvement, and chain values across tool calls deterministically.
Custom tools troubleshooting: Resolve common issues with custom tool integrations
Google Calendar Integration: Connect your assistant to Google Calendar for seamless appointment scheduling and availability checking.
Google Sheets Integration: Connect your assistant to Google Sheets for seamless data entry.
Slack Integration: Connect your assistant to Slack for seamless message sending.
GoHighLevel Integration: Connect your assistant to GoHighLevel for seamless appointment scheduling, contact creation, and availability checking.
Introduction to Knowledge Bases: Learn how to create and integrate custom knowledge bases into your AI assistants.
Using the Query Tool for Knowledge Bases: Learn how to configure and use the query tool to enhance your AI assistants with custom knowledge bases.
Custom Knowledge Base: Create and implement your own knowledge base server for full control over document retrieval
Tool Arguments Encryption: Learn to encrypt tool arguments and protect sensitive data
Deepgram Keywords and Keyterm Prompting: Boost STT accuracy for domain words and phrases
Custom voices: Use a custom voice with your preferred provider
ElevenLabs: Set up a custom ElevenLabs voice in Vapi
PlayHT: Set up a custom PlayHT voice in Vapi
Custom transcriber: Integrate your own transcription service with Vapi
Custom TTS integration: Learn to integrate your own text-to-speech system with VAPI
Fine-tuned OpenAI models: Use Another LLM or Your Own Server
Connecting Your Custom LLM to Vapi: A Comprehensive Guide
Custom LLM Tool Calling Integration
Appointment scheduling assistant: Build a voice AI appointment scheduling assistant with Google Calendar integration, availability checking, and automated confirmations using Vapi Assistants.
Lead qualification assistant: Build a voice AI outbound sales assistant with BANT data capture, CRM integration, objection handling, and automated follow-ups using Vapi Assistants.
Inbound customer support: Build a voice AI banking support agent with tools for account lookup, balance and transaction retrieval.
Web Snippet: Easily integrate the Vapi Voice Widget into your website for enhanced user interaction.
Documentation agent: Build a voice assistant that answers questions about your docs
Customer support escalation system: Build a voice AI customer support system with dynamic escalation that routes calls based on customer data, issue type, and real-time agent availability using transfer tools and webhooks.
Multilingual support agent: Build a multilingual voice AI customer support agent with automatic language detection, native voices, and comprehensive tools for international customer service
Evals quickstart: Get started with AI agent testing in 5 minutes
Advanced eval testing: Master testing strategies and best practices for production AI agents
Simulations quickstart: Test your AI assistants with realistic AI-powered callers
Simulations advanced: Master testing strategies and best practices for AI voice agent simulations
Boards quickstart: Create custom analytics dashboards in minutes
Structured outputs quickstart: Get started with structured data extraction in 5 minutes
Structured outputs examples: Real-world examples and templates for common use cases
Scorecard quickstart: Automatically grade calls against KPIs using structured outputs
Monitoring quickstart: Set up automated quality monitoring for your voice AI agents
Configuring Inbound and Outbound Calls for Squads: Configuring assistants for inbound/outbound calls.
Introduction to Squads (Multi-Assistant Conversations): Use Squads to handle complex workflows and tasks.
Handoff tool: Transfer the call to another assistant, squad, or dynamically determined destination.
Passing data between assistants: Three approaches for forwarding context to the next assistant in a squad — when to use each, and what each one costs.
Clinic triage with handoff tools: Build a multi-assistant clinic experience with specialized assistants for triage, emergency handling, and scheduling using handoff tools.
Clinic triage and scheduling squad: Build a multi-assistant clinic experience with specialized assistants for triage, emergency handling, and scheduling using Squads.
E‑commerce order management squad: Build a multi-assistant experience for order tracking, returns processing, and VIP handling using Squads.
Property management routing squad: Build a property management Squad with a router assistant plus maintenance and leasing specialists for accurate transfers.
Multilingual support squad: Build a Squad with dedicated English, Spanish, and French assistants and a language selection entrance flow.
Silent Handoffs
Voice AI Prompting Guide: How to write effective prompts for voice AI assistants
Debugging voice agents: Learn to identify, diagnose, and fix common issues with your voice assistants and workflows
Enterprise environments (DEV/UAT/PROD): Promotion and configuration management for assistants and squads
IVR Navigation: How to navigate IVR menu systems effectively
Test Suites: End-to-end test automation for AI voice agents
Chat Testing: Automated text-based testing for AI agents
Voice Testing: Automated voice call testing for AI voice agents
Creating Free Phone Numbers: Creating free phone numbers on the Vapi platform.
Inbound SMS: Let agents auto-start chats from incoming text messages (US only)
Import number from Twilio: Import a new or existing number from Twilio
Import number from Telnyx: Import and use your Telnyx numbers with Vapi
SIP introduction: Make SIP calls to your Vapi assistant
SIP Trunking: How to integrate your SIP provider with Vapi
SIP networking and firewall configuration: Learn to configure your network to allow SIP signalling and media traffic with Vapi
Twilio SIP Integration: How to integrate Twilio SIP with Vapi
Telnyx SIP integration: How to integrate SIP Telnyx to Vapi
Zadarma SIP Integration: How to integrate SIP Zadarma to Vapi
Plivo SIP Integration: Learn to connect your Plivo SIP trunk to Vapi for inbound and outbound calls
Amazon Chime SDK SIP Integration: How to integrate Amazon Chime SDK Voice Connector with Vapi
Troubleshoot SIP trunk credential errors: Learn to resolve gateway creation failures when setting up a BYO SIP trunk
Phone Number Hooks
Phone Calling: Learn how to create and configure phone numbers with Vapi
Outbound Calling: Learn how to send outbound calls from Vapi.
WebSocket Transport: Stream audio directly via WebSockets for real-time, bidirectional communication
Live Call Control
Customer Join Timeout: Set maximum time for users to join web calls before automatic termination
Voicemail Detection
Call Forwarding
Assistant-based warm transfer: Use AI assistants to facilitate call transfers
Dynamic call transfers: Learn how Vapi's dynamic call transfers work and explore implementation patterns for intelligent call routing.
Call Handling with Vapi and Twilio
Debug call forwarding drops: Learn to troubleshoot calls that drop immediately after initiating transfer
Call queue management with Twilio: Build a call queue system using Twilio to handle large volumes of calls while respecting Vapi concurrency limits, ensuring no calls are dropped.
Understanding Call Concurrency: Learn how concurrency slots work, how to stay within the default limit, and how to raise capacity for larger campaigns.
Call ended reasons: All possible call ended reason codes and what they mean.
Troubleshoot call errors: Learn to diagnose failed calls based on what the caller experienced.
Call analysis: Summarize and evaluate calls automatically
Call recording, logging and transcribing: Learn how to configure artifact plans to record calls, generate transcripts, and store logs for analysis
Outbound campaigns quickstart: Build a simple personalized outbound campaign that conducts post-service feedback and follow-up calls to improve customer experience
Outbound campaigns overview: Learn how to efficiently schedule calls, manage recipients, analyze performance metrics, and review detailed call logs and transcripts with Vapi's Outbound Call Campaigns
Chat quickstart: Build your first text-based conversation with a Vapi assistant in 5 minutes
Streaming chat: Build real-time chat experiences with token-by-token responses like ChatGPT
Non-streaming chat: Build reliable chat integrations with complete response patterns for batch processing and simple UIs
OpenAI compatibility: Seamlessly migrate existing OpenAI integrations to Vapi with zero code changes
Session management: Maintain conversation context using previousChatId vs sessionId
Variable substitution in sessions: Learn how template variables behave with sessions and chats
SMS chat: Enable text-based conversations with assistants via SMS messaging
Web widget: Add AI chat and voice capabilities to any website with a simple embeddable widget
Server URLs: Learn how to set up your server to receive and respond to messages from Vapi.
Setting server URLs: Learn about where you can set server URLs to handle call events.
Server events: Learn about different events that can be sent to a Server URL.
Spam call rejection: Screen inbound calls and reject known spam using your Server URL
Developing locally: Learn how to receive server events in your local development environment.
Server authentication
Workflows quickstart: Build a simple agent that greets users and gathers basic information using Vapi workflows.
Workflows overview: Learn to create robust, deterministic conversation flows with a visual builder.
Appointment scheduling workflow: Build a voice AI appointment scheduling workflow with calendar integration, availability checking, and automated confirmations using Vapi's workflow builder.
Lead qualification workflow: Build a voice AI outbound sales workflow with lead qualification, CRM integration, and automated follow-up using Vapi's visual workflow builder.
Clinic triage and scheduling workflow: Build a voice AI clinic workflow with medical triage protocols, appointment booking, and emergency routing using Vapi's visual workflow builder.
E-commerce order management workflow: Build a voice AI e-commerce workflow with order tracking, return processing, and customer support automation using Vapi's visual workflow builder.
Property management call routing: Build a voice AI property management system with dynamic call routing that determines destinations based on tenant verification, inquiry type analysis, and real-time agent availability using workflow API requests.
Multilingual support workflow: Build a multilingual voice AI customer support workflow with language selection, dedicated conversation nodes, and cultural context using Vapi's workflow builder.
Frequently Asked Questions: Frequently asked questions about Vapi.
Core Models: Learn about the three core components to Vapi's voice AI pipeline.
Orchestration Models: Learn about the real-time models Vapi runs on top of STT, LLM, and TTS.
Vapi Voices: Our curated selection of high-quality voices
Legacy voice migration guide: Legacy Vapi Voices were retired on March 1, 2026. Here's what changed and how to update if needed.
ElevenLabs: How Vapi Integrates Text-to-Speech Platforms?
PlayHT
Azure
OpenAI
Cartesia
LMNT
Minimax: Configure Minimax TTS voices and word-level subtitle timing
RimeAI
Deepgram
Inworld
OpenAI: What is OpenAI?
Azure OpenAI: Use custom Azure OpenAI instances with your own rate limits and configurations
Anthropic Bedrock: Use Anthropic Claude models via AWS Bedrock with your own AWS resources
Gemini by Google: What is Gemini?
Groq: What is Groq?
DeepInfra: DeepInfra is a provider for Vapi.
Perplexity: What is Perplexity.ai?
TogetherAI: TogetherAI is a provider for Vapi.
OpenRouter: What is OpenRouter?
Deepgram: What is Deepgram?
Google
Gladia
Speechmatics
Talkscriber: What is Talkscriber?
AssemblyAI
AWS S3: Store recordings of chat conversations in AWS S3
GCP Cloud Storage: Store recordings of chat conversations in GCP Cloud Storage
Cloudflare R2: Store recordings of chat conversations in Cloudflare R2
Supabase S3 Storage: Store recordings of chat conversations in Supabase Storage
Langfuse Integration with Vapi: Integrate Vapi with Langfuse for enhanced voice AI telemetry monitoring, enabling improved performance and reliability of your AI applications.
Voiceflow: Vapi x Voiceflow
ChatDash Integration with Vapi: ChatDash is a white-label dashboard platform that integrates with Vapi to provide analytics, call logs, and Stripe billing for AI agent agencies.
Vapify Integration with Vapi: Vapify is a white-label dashboard for Vapi. It helps you turn your agency into a voice AI powerhouse—without writing a single line of code.
Voicerr AI - Whitelabel AI Voice Agents: Voicerr AI is a Vapi-powered voice platform that lets agencies brand dashboards, automate billing, launch campaigns, and run full call-center operations at unlimited scale.
VoiceAIWrapper Integration with Vapi: White-Label Vapi Integration | Launch Your Voice AI Agency in 30 Minutes
Sympana Connector: Native GoHighLevel automation for Vapi agents
Support: We are open to all kinds of help inquiry, feedback and feature request, help inquiry.
How to Report Issues Effectively: Learn how to structure your issue reports for fast and accurate resolution
Vapi Enterprise: Build and scale with Vapi.
Definitions: Useful terms and definitions for Vapi & voice AI applications.
RSS Feed: Stay updated with the latest incidents from Vapi or third party providers
Data Flow: Understand how data flows through Vapi when using custom storage and custom models
JWT Authentication: Secure API authentication guide
Recording consent plan: Learn how to configure recording consent plans to ensure compliance with privacy laws and regulations
GDPR Compliance: Learn how Vapi ensures GDPR compliance for its voice assistant platform.
HIPAA Compliance: Learn how to ensure privacy when using Vapi's voice assistant platform.
Retrieve call artifacts: Download recordings and call logs from Vapi's private storage using authenticated, short-lived URLs.
PCI Compliance: Ensure secure payment data handling while using Vapi’s voice assistant platform.
Proxy server guide: Keep assistant configs and API keys on your backend. Route Web SDK calls through your proxy.
Static IP addresses: Whitelist Vapi IP addresses
TCPA Consent Guide: Understanding consent requirements for outbound calls using Vapi's voice agent service.
Model Context Protocol (MCP) Integration: Connect your assistant to dynamic tools through MCP servers for enhanced capabilities.
Vapi MCP Server: Connect Vapi to AI assistants with Model Context Protocol (MCP)
Ecosystem: Find all of our resources here.
Project integration: Initialize Vapi in your existing projects with intelligent auto-detection
MCP integration: Turn your IDE into a Vapi expert with Model Context Protocol
Local webhook testing: Forward webhooks to your local development server with vapi listen
Authentication management: Manage multiple Vapi accounts and environments with the CLI
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