# Understand end users and identity

Map your customers to MindCloud end users and use the correct ID and credentials across Embedded API, MCP, and SDK.

An **end user** is one customer in your product. MindCloud gives that person an ID such as `enduser_...`. Store that ID beside your own user ID. Use it for later SDK, API, or MCP requests.

Create the end user from your backend with [POST /v1/users](/docs/embedded/embedded-api/api-reference/create-an-end-user). The `externalId` field can hold your own stable user ID. The create endpoint inserts a new record on every successful call, so store the returned `userId` and reuse it. Do not create a new end user for every session.

An API key identifies your organization. An end-user token authorizes SDK and legacy installation requests for one end user. Embedded MCP instead takes the end-user ID in its URL and uses your server's API key. These are different credentials. See [Get an end-user token](/docs/embedded/embedded-api/api-reference/get-an-end-user-token) when your SDK or installation API needs one.

Do not use an `externalId` where an endpoint asks for a MindCloud end-user ID. For example, the [Embedded MCP URL](/docs/embedded/embedded-mcp/quickstart) requires the returned `enduser_...` ID.