# Concepts

> How ActuallyCare's integration surface fits together: API vs MCP, authentication, the data model, and webhooks.

<!-- Source: https://docs.actuallycare.com/concepts -->

The thinking-clearly pages. Read these when you want to understand how the
pieces fit together, before (or instead of) memorizing endpoints.

## [API vs MCP](/concepts/api-vs-mcp)

Two ways to integrate — when to use the REST API, when to use the MCP server,
and how to combine them.

## [Authentication model](/concepts/authentication)

The three credential types — OAuth for Claude users, API keys for servers,
JWTs for user sessions — and when each applies.

## [Data model](/concepts/data-model)

The entities behind your CRM — contacts vs clients vs leads, transactions,
the vendor pipeline, property management, and how visibility follows the
team/brokerage hierarchy.

## [Webhooks](/concepts/webhooks)

Event-driven integration: the self-documenting event catalog, payload
signatures, and delivery semantics.