Explanation of Benefits – Is There Required Information It MUST Include?

So I’ve had a few medical procedures lately (I’m fine) and OMG what is going on with the billing/insurance?? My Explanations of Benefits don’t contain a description of service, and the procedure codes they DO have are copyrighted by the AMA & unavailable to us peons. I literally cannot find out what the Explanation of Benefits is even explaining; I have to get a bill (not always sent, esp if I don’t owe anything) or query the provider, whose contact phone number doesn’t appear on the EOB and whose name on the EOB may not correlate with the name of the provider as I know it. For ex, an EOB that carries the name of the contractor that provides the service to the practice doesn’t help me at all.

It’s 100% black box medical payments to uncertain entities for unknown procedures, that we’re told a million times we need to check carefully for accuracy using information that apparently we can’t get.
¯\_(ツ)_/¯ oh well! Hope there’s no mistakes anywhere! LOL LMAO etc

Question: Is there a *requirement* for the Explanation of Benefits to include plain-language service description and contact information for the payee? Because the CMS.gov website, which describes the parts of an EOB, seems to imply there is a standard which my EOBs aren’t meeting. If there is such a requirement, what steps can I take to complain about my insurance co not providing this info?

Thanks for any help. I’m really baffled by this – why would the insurer not want me to be able to tell who was being paid & for what on my behalf?