> For the complete documentation index, see [llms.txt](https://learn.mechanic.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://learn.mechanic.dev/platform/shopify/custom-authentication.md).

# Custom authentication

In extraordinary cases, Mechanic can be configured to route Shopify API requests through a [custom Shopify app](https://help.shopify.com/en/manual/apps/app-types/custom-apps). This may be necessary when a store's Mechanic tasks need to perform work in a way that is only possible via a custom app (e.g. accessing select Shopify APIs, or working with a Shopify API rate limit negotiated for a specific custom app).

## Configuration

Shopify Plus accounts can configure this in the Permissions section of the store's Mechanic settings.

Before saving a new access token, you must ensure that the custom app has every access scope that Mechanic requires.


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