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

# Metadata

> Find all the Mailchimp API documentation and tools developers need to send marketing and transactional emails.


## API Docs

- Metadata [List custom metadata fields](https://mailchimp.com/developer/transactional/api/metadata/list.md)
- Metadata [Add custom metadata field](https://mailchimp.com/developer/transactional/api/metadata/add.md)
- Metadata [Update custom metadata field](https://mailchimp.com/developer/transactional/api/metadata/update.md)
- Metadata [Delete custom metadata field](https://mailchimp.com/developer/transactional/api/metadata/delete.md)

## OpenAPI Specification

The raw OpenAPI 3.1 specification for this API is available at:
- [OpenAPI JSON](https://mailchimp.com/developer/openapi.json)
- [OpenAPI YAML](https://mailchimp.com/developer/openapi.yaml)