Requests carrying the bare user agent Trello are attributed to the link preview fetcher behind Trello, the Atlassian work management board product, which retrieves page metadata when a person pastes a URL onto a card so Trello can render a link card with a title, description and thumbnail. Atlassian does not document this user agent anywhere in its Trello or developer documentation, and it publishes no IP ranges or reverse DNS hostnames for the fetcher. The user agent is a single bare word with no version, product URL or contact address, which makes it weak evidence of origin and trivially spoofable, so this entry is matched only against a user agent consisting of that word alone, to avoid capturing a person browsing inside the Trello application.

At a glance

Operator: Atlassian
Type: Preview

How Centinel checks it

User agent: The request calls itself this crawler. Anyone can send the same string.

Trello Link Preview publishes nothing Centinel can check a source against, so a match reports the name and leaves the source unconfirmed. The match tokens, verification domains, and address feeds are not published here.

Allowing or blocking it

The crawler object in the /validate response sets access_allowed to true only for a verified source that your tenant allowlists. A policy rule can allow or block this crawler by its category, Preview.

Back to the crawler catalog