倘若我没记错，500 是 JSON-RPC 错误响应规定使用的状态码。回复的正文里仍有 JSON 响应，说明错误的具体原因，譬如 {"result":"","error":"bitcoin address not found","id":"1"}。
ORIGINAL · 英文原文
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"}.