> This page is for Personalization.

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

# Cookie policy

> The cookie policy for Contentful Personalization.

## Overview

Using any of our JavaScript SDKs will add the following `localStorage` items:

* `nt_anonymous_id`

* `nt_experiences`

* `nt_profile`

If you decide to use the [Privacy Plugin](/personalization/privacy-plugin), the plugin will also set the following `localStorage` item:

* `nt-consent`

If you opt to use Ninetailed server-side, your implementation may add this cookie:

* `ntaid`

Ninetailed does not set any `sessionStorage` keys. For reference, each of these strings are visible in our [open-source SDKs](https://github.com/ninetailed-inc/experience.js/blob/eb4697294c0fdd43c6871ddcf28d094b08a1cd12/packages/sdks/shared/src/lib/constants.ts#L4).