Flyweight User Agent: Our Web Crawler

The Flyweight crawler is operated by Flyweight GmbH. It reads the public pages of online stores whose owners have installed our AI shopping assistant, so the assistant can answer shoppers’ questions using the store’s products, policies and help content.

If you found this page through your access logs, here is how to identify, allow or stop the crawler.

Why it is visiting your site

We crawl a domain only after someone installs Flyweight on that store and connects the domain as a content source. We do not crawl the open web or follow links outside the connected domain.

Crawls run when a store is first connected and when its content is refreshed, rather than continuously. If the visit is unexpected, someone on your team may have installed the app from the Shopify App Store.

How to identify it

Every request includes this token at the end of its User-Agent header:

Flyweight/1.0 (+https://flyweight.io/user-agent)

The crawler uses a real Chrome browser to render pages as a shopper would see them. A complete example:

Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/143.0.0.0 Safari/537.36 Flyweight/1.0 (+https://flyweight.io/user-agent)

The Chrome version changes with browser updates. Match the substring Flyweight/, not the full header or a specific Chrome version.

Earlier user agent

Until September 2026 the crawler identified itself with a different token:

FlyweightBot/1.0 (+https://flyweight.io/bot)

We changed it because some bot protection services challenge or block any user agent that contains the word “bot”. If you allowlisted FlyweightBot, update the rule to match Flyweight/. Rules on the IP address below need no change.

Where the requests come from

Crawl traffic currently leaves through a single static IP address dedicated to us:

52.212.232.38

The IP address is the more precise signal for an allowlist. The token identifies the crawler even if we add another crawl route. If a tool only accepts a user agent, use Flyweight/, keeping the spoofing limitation below in mind.

How to allow it

In Cloudflare, create a WAF custom rule with the Skip action. To match the IP address:

(ip.src eq 52.212.232.38)

To check both the user agent and the IP address:

(http.user_agent contains "Flyweight/" and ip.src eq 52.212.232.38)

Anyone can copy the Flyweight/ token into a User-Agent header. Use a user-agent-only rule only where no more precise option is available, and prefer a narrowly scoped action over a blanket Skip:

(http.user_agent contains "Flyweight/")

Other WAFs and CDNs offer equivalent allow or bypass rules. In nginx, the classification must be used by a rule to take effect:

map $http_user_agent $blocked_bot {
    default                      0;
    "~*(bot|crawler|headless)"   1;
    "~*Flyweight/"               0;
}

server {
    if ($blocked_bot) {
        return 403;
    }
}

Shopify fraud filters, country blockers and bot blockers often provide an allowlist. Add the IP address above, or Flyweight/ if the field accepts a user agent. A block can cause the assistant to answer with missing or outdated content.

How to stop it

The crawler does not currently read robots.txt, so a rule there will not stop it. Remove the domain as a content source in the Flyweight admin or uninstall the app to stop further crawls being scheduled. A crawl already in progress finishes its current batch, usually within a few minutes.

You can also block requests at your WAF or CDN using the expressions above with a block action. Contact us first if possible, as blocking the crawler prevents the assistant from refreshing its knowledge of your store.

Contact

Questions about the crawler or requests to stop crawling a domain you administer: hello@flyweight.io. We answer these directly.

Flyweight GmbH, Jungbuschstraße 28, 68159 Mannheim, Germany. Legal notice.