> ## Documentation Index > Fetch the complete documentation index at: https://docs.contextual.ai/llms.txt > Use this file to discover all available pages before exploring further. # Glossary > Essential definitions for understanding and using Contextual AI ## Agent An **Agent** is a queryable AI application that retrieves relevant data from connected **datastores** and generates responses grounded in that data. Agents are built in the Contextual AI app using **Agent Composer**: you choose a template (e.g. Basic Search, Agentic Search) or design a custom workflow with nodes and steps. Agents can do multi-step retrieval, use tools (search, APIs, MCP), and produce cited answers. You create and manage agents [via the API](/api-reference/agents/create-agent) or the [platform UI](/quickstarts/platform-gui). ## Agent Composer **Agent Composer** is the framework for building agents on Contextual AI. You compose workflows from building blocks (search steps, generation steps, tools, conditional logic) either by editing **YAML** or using the visual workflow builder. Self-serve users can use **Basic Search** and **Agentic Search** templates; enterprise users get access to the full builder and additional templates. See [Agent Composer overview](/reference/ac-overview) and [Agent Composer templates](/how-to-guides/agent-composer-templates). ## Attributions / Citations **Attributions** (citations) are in-line references that credit the sources used to generate a response. When you query an agent, attributions appear for factual claims (e.g. \[1], \[2]) and link to the retrieved documents. You can view them in the API response or in the UI. Agents built with Agent Composer can be configured to enforce citation format (e.g. [number]() with a References section). See [core system prompt](/reference/core-system-prompt) and [disable commentary](/reference/disable-commentary). ## Chunking **Chunking** is the process of splitting documents into smaller, semantically meaningful pieces so the agent can retrieve and reason over them. Contextual AI supports multiple chunking modes to suit different document types. See [Chunking configurations](/reference/chunking). ## Connector A **connector** links an external data source (e.g. Confluence, Google Drive, SharePoint, Box) to Contextual AI. Content is synced into one or more **datastores** and kept up to date. See [Connectors overview](/connectors/overview). ## Datastore A **datastore** is a repository of ingested content (documents, chunks) that an **agent** searches when answering queries. You connect datastores to an agent when building the agent; one agent can use multiple datastores, and one datastore can serve multiple agents. Content is added via [connectors](/connectors/overview), [local upload](/connectors/local-file-upload), or the [documents API](/api-reference/datastores-documents/ingest-document). See [Datastores reference](/reference/datastores). ## Document A **document** is a single unit of content (e.g. PDF, HTML, Markdown) ingested into a **datastore**. After ingestion, documents are parsed, chunked, and indexed for retrieval. You ingest documents [via the API](/api-reference/datastores-documents/ingest-document) or via connectors. ## Knowledge (retrievals) **Knowledge** (or **retrievals**) is the set of chunks and sources the agent retrieved from its **datastores** to generate a response. In Agent Composer workflows, search steps output retrievals that are passed to generation steps. Responses can include **attributions** pointing to these sources. ## LMUnit **LMUnit** is an evaluation method that uses natural-language unit tests to check specific qualities of an agent’s response (e.g. “Is the response succinct?” or “Is the complexity appropriate for the audience?”). You define and run these tests [via the LMUnit API](/api-reference/lmunit/lmunit). See also [LMUnit overview](https://contextual.ai/blog/lmunit/). ## Node In **Agent Composer**, a **node** is a single step in the workflow graph (e.g. a search step, a generation step, a tool call). Nodes are connected by **input mapping** from outputs of one node to inputs of another. See [YAML format](/reference/ac-yaml-format) and [node reference](/how-to-guides/ac-node-reference). ## Query / Prompt The **query** (or **prompt**) is the user’s question or instruction sent to an **agent**. You submit queries [via the query API](/api-reference/agents-query/query) or through the platform UI. The agent uses this input to drive retrieval and generation. ## RAG **Retrieval Augmented Generation (RAG)** is a technique that grounds LLM outputs in retrieved knowledge. Contextual AI agents use RAG: they search your **datastores**, then generate responses from the retrieved chunks, with **citations**. Agent Composer lets you configure retrieval (e.g. search steps, reranking, filters) and generation (e.g. system prompts, model choice) in one workflow. ## Response The **response** is the agent’s answer to a **query**. It is generated from **retrievals** and can include **attributions** and a References section. Response behavior is controlled by the agent’s workflow and generation config (e.g. [max tokens](/reference/max-new-tokens), [temperature](/reference/temperature)). ## System Prompt The **system prompt** (and, when no retrieval is used, the **no-retrieval system prompt**) defines the agent’s behavior and how it should use retrieved content. You set these when building an agent in Agent Composer. See [Core system prompt](/reference/core-system-prompt) and [No-retrieval system prompt](/reference/no-retrieval-system-prompt). ## Template A **template** is a pre-built Agent Composer workflow. **Basic Search** and **Agentic Search** are available for self-serve users; additional templates (e.g. Device Log Analysis, domain-specific templates) are available for enterprise. See [Agent Composer templates](/how-to-guides/agent-composer-templates) and [Template catalog](/examples/templates-catalog). ## Workspace A **workspace** is the top-level container for your **agents**, **datastores**, API keys, and other resources. Access and billing are managed at the workspace level.