Will the AI use trending topics when it writes my social media posts?

The AI follows your instructions. The skills do not pull data about what is trending or what gets the most likes.

To bring that data in, you can use a paid service such as Apify, or tell the AI to go to Reddit, find a few communities in your industry, collect the posts with the most upvotes, and use them to write your posts. If you run Claude Cowork on your computer, it can use your browser to gather this for you, with no cost beyond your Claude subscription.