# API Concepts Developer Docs

> Learn how pagination, errors, idempotency, and versioning work before you connect Mailrith to a sync flow.

- Human page: https://mailrith.com/developers/category/api-concepts
- Markdown page: https://mailrith.com/developers/category/api-concepts.md
- Guide count: 5
- Last updated: 2026-07-13
- Related keywords: API Concepts, API Concepts developer docs, Mailrith developer docs, Mailrith public API, Pagination, Errors, Idempotency, Versioning, Consent And Privacy API Boundaries

Agent notes:
- Use these category links to choose the most specific Mailrith developer guide before writing integration code.
- Use the OpenAPI document for exact request and response schemas.

## Guides
- [Pagination](https://mailrith.com/developers/pagination.md): Mailrith uses cursor pagination across list endpoints. This guide explains how to request the first page, continue with `next_cursor`, resume interrupted syncs, and reuse the same pagination pattern across subscribers, tags, custom fields, forms, and segments.
- [Errors](https://mailrith.com/developers/errors.md): Non-2xx responses include stable error codes and plain-language messages. This guide explains how to log errors, avoid matching on message text, map status codes to user or system actions, and retry only when the same request may succeed later.
- [Idempotency](https://mailrith.com/developers/idempotency.md): Import and export job creation endpoints accept idempotency keys so network retries do not queue duplicate work. This guide explains when to use a key, how to choose one, and how to store the key with your own job record.
- [Versioning](https://mailrith.com/developers/versioning.md): Mailrith versions the public API in the path. This guide explains the `/v1` contract boundary, which base URLs to call, how to avoid unversioned paths, and how to compare future API versions before you upgrade.
- [Consent And Privacy API Boundaries](https://mailrith.com/developers/consent-and-lawful-basis.md): The public Subscriber API stores profile and list-management data, not separate consent-evidence fields. This guide explains the API boundary, safe Subscriber upserts, imports, webhooks, and when to use Mailrith-hosted GDPR consent workflows.