Code,Description,Reference
2.00,Unassigned,
2.01,Created,[RFC7252]
2.02,Deleted,[RFC7252]
2.03,Valid,[RFC7252]
2.04,Changed,[RFC7252]
2.05,Content,[RFC7252]
2.06-2.30,Unassigned,
2.31,Continue,[RFC7959]
3.00-3.31,Reserved,[RFC7252]
4.00,Bad Request,[RFC7252]
4.01,Unauthorized,[RFC7252]
4.02,Bad Option,[RFC7252]
4.03,Forbidden,[RFC7252]
4.04,Not Found,[RFC7252]
4.05,Method Not Allowed,[RFC7252]
4.06,Not Acceptable,[RFC7252]
4.07,Unassigned,
4.08,Request Entity Incomplete,[RFC7959]
4.09,Conflict,[RFC8132]
4.10-4.11,Unassigned,
4.12,Precondition Failed,[RFC7252]
4.13,Request Entity Too Large,[RFC7252][RFC7959]
4.14,Unassigned,
4.15,Unsupported Content-Format,[RFC7252]
4.16-4.21,Unassigned,
4.22,Unprocessable Entity,[RFC8132]
4.23-4.28,Unassigned,
4.29,Too Many Requests,[RFC8516]
4.30-4.31,Unassigned,
5.00,Internal Server Error,[RFC7252]
5.01,Not Implemented,[RFC7252]
5.02,Bad Gateway,[RFC7252]
5.03,Service Unavailable,[RFC7252]
5.04,Gateway Timeout,[RFC7252]
5.05,Proxying Not Supported,[RFC7252]
5.06-5.07,Unassigned,
5.08,Hop Limit Reached,[RFC8768]
5.09-5.31,Unassigned,