> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Chainstack updates: October 7, 2026

> Multichain API lets you use one API key across the Global Nodes and Dedicated Nodes you attach to a single endpoint.

**Multichain API**. You can now use one API key across several chains. See [Use one API key across multiple chains with Multichain API](/docs/multichain-api) for the full guide. A multichain endpoint holds the [Global Nodes](/docs/global-elastic-node) and [Dedicated Nodes](/docs/dedicated-node) you attach to it, and its API key authorizes requests to every attached node. Instead of managing one key per node, you keep one secret in your environment variables or CI.

**Set up an endpoint**. On Chainstack, click **Multichain API** > **Create endpoint** and name the endpoint. On the endpoint page, click **Add node** to attach nodes. You can add or remove nodes at any time, and the API key stays the same. Under **Connection details**, select a node to copy its HTTPS and WSS endpoint URL, which already contains the key.

**API key**. The key starts with `mt_`, and you can copy the full value from the endpoint page at any time. To replace a key, create a new endpoint with the same nodes, update your applications, and delete the old endpoint. Key rotation on an existing endpoint is not available.

**Attachment rules**. An endpoint can hold one Global Node per protocol and network and any number of Dedicated Nodes. Regional Nodes can't be attached. The same node can belong to several endpoints. When you delete a node on Chainstack, it is removed from its endpoints automatically, and the endpoint and its key stay.

**Requests**. A request that uses the key on a chain whose node is not attached to the endpoint returns `401 Unauthorized`. Each request follows the rate limits and access settings of the node it targets.

**Delete an endpoint**. Click **Delete endpoint** to revoke the key on every attached node. This action can't be undone.

**Availability**. Multichain API is available on every plan, including Developer.