bitcoind not responding to RPC

If I recall correctly, 500 is the prescribed status code for JSON-RPC error responses.  There is still a JSON response in the body of the reply telling the explanation of the error, which could be something like {“result”:"",“error”:“bitcoin address not found”,“id”:“1”}.

Can anyone confirm if JSON-RPC over HTTP is supposed to use status 500 if the reply is an error reply?  I can’t remember where I picked that up, maybe it’s wrong.  It seems like 200 would make more sense unless there’s something wrong with the mechanics of the HTTP request itself.  (and maybe that’s what it said and I forgot and spread 500 to all error responses)