100% agreed. I use Claude Code to write 90% of my code at this point, but have found that it is genuinely worse than a junior at writing meaningful test cases. Most of the time it will make up interfaces or mock things incorrectly etc to the point where I just give up and write them myself. The bulk of the “tests” it writes test things which are meaningless (does the interface exist etc). This is with typescript + vitest with opus 4.5.