# Documentation

## Getting Started

- [Introduction](https://twentytwo.documentationai.com/introduction.md): Learn how to build and trigger AI voice calls with Twenty2, including assistants, API calls, and call tracking.
- [Authentication](https://twentytwo.documentationai.com/authentication.md): Learn how to authenticate your requests to the Twenty2 API.
- [Quick Start](https://twentytwo.documentationai.com/quickstart.md): Make your first outbound call in 3 steps.
- [Errors & Rate Limits](https://twentytwo.documentationai.com/errors-rate-limits.md): Understand error responses and rate limits in the Twenty2 API.
- [FAQ](https://twentytwo.documentationai.com/help-center/faq/how-to-integrate-twentytwo.md): Answers to the most common questions about using and integrating Twenty2.
- [Troubleshooting](https://twentytwo.documentationai.com/help-center/troubleshooting/webhook-not-triggering.md): Fix common issues with calls, webhooks, phone numbers, and the Twenty2 API.

## API

- [Initiate a Call](https://twentytwo.documentationai.com/api-reference/initiate-call.md): Trigger a single outbound call using a published assistant. Calls are non-blocking — the API returns immediately once the call is queued.
- [List Calls](https://twentytwo.documentationai.com/api-reference/list-calls.md): Retrieve a paginated list of past calls with optional filters.
- [Get Call Detail](https://twentytwo.documentationai.com/api-reference/get-call-details.md): Retrieve full details for a single call including transcript, recording, and output variables.

## Webhooks

- [Webhooks](https://twentytwo.documentationai.com/webhooks.md): Get notified instantly when a call completes via webhook events.