When I was trying to use Claude to analyze my past transactions, I found out that it was constantly hallucinating charges, sometimes adds new, double counts and etc.

When I'm dealing with my finances the 95% time Claude is correct and doesn't hallucinate is not enough as I have to be vigilant and review its work all the time. So it kinda makes it worthless in this case for me

Give GPT in Codex a try! I agree, Claude still seems quite prone to hallucinations, especially with incomplete or limited datasets.