Haddop API

Hi, I want to know if there is a hadoop API that can give me the details about the resources used by all the hadoop nodes: indeed, I want to know the total, used and available capacity for RAM, CPU and disk for all Hadoop nodes. I tested this API "http://nm-http-address:port/ws/v1/node", but it sends me information that has no link with the real resources used by the machine and I don't know from what source this API gets this information. Thanks for your answers