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

# Crawler Signatures

> Enable authenticated image fetching from Shopify using HTTP signatures, with automatic proxy fallback so Layers can sync product media reliably at scale.

## Overview

Crawler Signatures let Layers authenticate its image crawler when fetching media from your Shopify store. Stores with larger catalogs may hit rate limits from automated requests crawling all of the catalog images. By attaching HTTP signature headers, Layers can fetch images more reliably and avoid unnecessary blocking.

## Configuration

1. In the Layers dashboard, go to **Settings → Shopify Sync**.
2. Under “Crawler Signatures”:
   * Enable Crawler Signatures
   * Signature-Input Header
   * Signature Header
3. Click Save.

Notes:

* When enabled, both Signature-Input Header and Signature Header are required.
* Use the exact values provided by Shopify.

## How it works

When enabled, Layers adds the following headers to image requests:

* Signature-Input
* Signature
* A standard agent is also included to identify the request.

If a signed request fails (for example due to rate limiting or temporary errors), Layers automatically retries through a secure proxy - no action needed. This failover is automatic and helps ensure consistent image availability.

## Need help?

Contact [support@uselayers.com](mailto:support@uselayers.com).