I do not think it is accurate. If you are talking about ---> https://www.btcitrade.com/, the site relies on short-term moving averages for 3 weeks, 2 weeks, 1 week, and so on. This reliance will not be accurate in the long term because it gives a higher value to the short-term variables in exchange for lower values for long term variables.
Meaning that this tool is now accurate, but it fails to predict market trends because it monitors a very short range.