Derived from https://github.com/memcached/memcached/blob/master/doc/protocol.txt, just in this format for easy access
| Flag | Commands | Description |
|---|---|---|
| b | mg, ms, md, ma, me | Interpret key as base64 encoded binary value |
| c | mg, ms, ma | Return item CAS token |
| C(token) | ms, md, ma | Compare CAS value when storing/deleting |
| D(token) | ma | Delta to apply for arithmetic operation |