> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://developers.brevo.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://developers.brevo.com/_mcp/server.

# What are Brevo app extensions?

App extensions are how you customize your experience in Brevo, letting you bring your own functionality into both the backend and the Brevo frontend. A single app can be purely backend logic, purely custom UI components, or both. A Brevo App is the container for these extensions, managed with the [Brevo CLI](/docs/cli-reference) [](https://www.npmjs.com/package/@getbrevo/cli).

## Extension types

#### [OAuth apps](/docs/oauth-quickstart)

Authenticate with OAuth and call the Brevo API on behalf of a user from your own system.

#### [Action links](/docs/apps-action-links)

Create a custom UI component on a Brevo record that opens your website, passing its details as URL parameters.

#### [Brevo Functions](/docs/apps-brevo-functions)

Select from a template or generate it with AI to calculate contact attributes. ***Coming soon.***

#### [Iframe modals](/docs/apps-iframe-modals)

Embed your website in a modal that opens on top of a Brevo record. ***Coming soon.***

Looking for a pre-built plugin or data connector instead? That's a different type of app. Check the [Brevo App Store](https://app.brevo.com/app-store).

## Get started

New to Brevo Apps? Start here: it walks through installing the CLI and creating your first app.

#### [Create your first app](/docs/apps-getting-started)

Install the CLI and create your first Brevo app.

## Guides

* [Authenticating a backend app with OAuth](/docs/oauth-integration-guide)
* [Passing context through an action link](/docs/apps-action-links#receiving-the-records-details)
* [Manage your OAuth app scopes](/docs/oauth-scopes)
* [Managing apps from the CLI](/docs/cli-reference)

## Further reading

* [OAuth 2.0](/docs/oauth): how token-based authorization works for backend apps
* [CLI reference](/docs/cli-reference): every `brevo` command for managing apps