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

# API structure

> How the Marketing API is organized—REST conventions and the root URL.

The Marketing API generally follows REST conventions, with some deviations.

* *Resources* are typically nouns like `subscribers` or `campaigns`.
* *Subresources* can be multiply nested under resources.
* *Actions* are usually represented by [HTTP methods](/marketing/api-concepts/methods-and-parameters). Actions that do not correspond to HTTP methods are collected under an `actions/` subresource.
* *Responses* use the generic JSON content type.

We use the [OpenAPI Specification](https://www.openapis.org/) (formerly known as Swagger) to describe each endpoint. [The API self-description](https://api.mailchimp.com/schema/openapi/OpenAPI.json?expand) also contains type information to help you error-check your requests.

The root url for the API is `https://api.mailchimp.com/3.0/`. All API endpoints for your account are available relative to this URL.

For more details on how to query Marketing API endpoints, see [Methods and Parameters](/marketing/api-concepts/methods-and-parameters). For troubleshooting API calls, see the [Errors](/marketing/api-concepts/errors) docs.