The analysis tool just simply allows a player to place hypothetical stones on the board to help visualize possibilities. It’s really just a reading tool.
The score estimator does not tell a player specifically where to move, but it does show some things (like estimated territory and the score estimate itself) that I think could be interpreted as providing assistance of some sort. Personally, I don’t really like that feature and have advocated for its removal, however, currently it seems to be an accepted part of the site.
When setting up a game, there is an option to disable analysis, which disables both the analysis and score estimator tools.
Actually, there’s also been lively debate about whether the analysis tool should be allowed as well: