Perhaps by running an exit node
Why is this downvoted? This is a valid method for measuring frequency of visited sites. The exist node has to know the unencrypted destination to be able to provide the requested content.
exit nodes are not involved with accessing hidden services at all, so the suggestion is nonsense.
Using words is more helpful than merely down-voting things.
The Ahmia project publishes how they approach this problem, e.g. here:
https://github.com/ahmia/ahmia-crawler
Their repos also showcase how they're using blacklisting to keep from linking to CSAM.
Anyway, please beware that there is a not-insignificant propability that opening random tor hidden addresses lead to thinks you don't want to see like gore and CSAM.