> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bey.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Glossary

> Definitions of core Beyond Presence concepts and terms, in alphabetical order.

## Agent

Short form of [Conversational Video Agent (CVA)](#conversational-video-agent-cva), an AI system that combines an LLM or voice agent with an avatar for natural, face-to-face AI video conversations. See [Agents](/get-started/agents) for more info.

## API

Beyond Presence's REST API for programmatic access to agents, avatars, and conversations. See [API](/get-started/api) for more info.

## API Key

The credential used to authenticate API requests, sent via the `x-api-key` header. See [Authentication](/get-started/api#authentication) for more info.

## Avatar

An AI-generated digital clone of a person that gives an Agent its visual presence via face, expressions, lip-sync, and gestures. See [Avatars](/get-started/avatars) for more info.

## Call

Synonym of [Conversation](#conversation), see below.

## Conversation

One real-time dialogue session between a user and an agent; called a "Call" in the [API](/api-reference). See [Studio](/get-started/studio) for more info.

## Conversational Video Agent (CVA)

Long form of [Agent](#agent), see above.

## Custom Avatar

An avatar created from a customer's own training video, exclusive to their account. See [Custom Avatars](/get-started/avatars/custom) for more info.

## Knowledge Base

The aggregate collection of files an agent can reference during conversations to answer domain-specific questions. See [Knowledge Base](/get-started/studio#knowledge-base) for more info.

## Knowledge File

A single uploaded document that's part of an agent's knowledge base; the underlying API resource. See [API Reference](/api-reference) for more info.

## Managed Agent

A Conversational Video Agent fully hosted and run on Beyond Presence's infrastructure, with no customer infrastructure setup required. Beyond Presence provides managed agents at scale. See [Managed Agents](/integrations/managed-agents) for more info.

## Speech-to-Video API

A real-time API that converts an audio or speech stream into a synchronized, lifelike avatar video stream, letting customers add an avatar to a voice agent they build and run themselves, keeping full control over speech-to-text, language model, text-to-speech, and turn detection. One of Beyond Presence's two core products, alongside [Managed Agents](#managed-agent). See [Speech-to-Video](/integrations/speech-to-video) for more info.

## Stock Avatar

One of the professional avatars Beyond Presence provides to all accounts, ready for immediate use. See [Stock Avatars](/get-started/avatars/stock) for more info.

## Studio

The Beyond Presence no-code web app (at [app.bey.chat](https://app.bey.chat)) for creating and managing agents, avatars, and API keys. See [Studio](/get-started/studio) for more info.

## Webhook

An endpoint you configure to receive real-time events (new messages, conversation ended, etc.) from conversations with your managed agents. See [Webhook Events](/integrations/managed-agents/webhook-events) for more info.